denoland-deno/cli/tsc/dts/lib.deno.ns.d.ts

// Copyright 2018-2024 the Deno authors. All rights reserved. MIT license.

/// <reference no-default-lib="true" />
/// <reference lib="esnext" />
/// <reference lib="deno.net" />

/** Deno provides extra properties on `import.meta`. These are included here
 * to ensure that these are still available when using the Deno namespace in
 * conjunction with other type libs, like `dom`.
 *
 * @category Platform
 */
declare interface ImportMeta {
  /** A string representation of the fully qualified module URL. When the
   * module is loaded locally, the value will be a file URL (e.g.
   * `file:///path/module.ts`).
   *
   * You can also parse the string as a URL to determine more information about
   * how the current module was loaded. For example to determine if a module was
   * local or not:
   *
   * ```ts
   * const url = new URL(import.meta.url);
   * if (url.protocol === "file:") {
   *   console.log("this module was loaded locally");
   * }
   * ```
   */
  url: string;

  /** The absolute path of the current module.
   *
   * This property is only provided for local modules (ie. using `file://` URLs).
   *
   * Example:
   * ```
   * // Unix
   * console.log(import.meta.filename); // /home/alice/my_module.ts
   *
   * // Windows
   * console.log(import.meta.filename); // C:\alice\my_module.ts
   * ```
   */
  filename?: string;

  /** The absolute path of the directory containing the current module.
   *
   * This property is only provided for local modules (ie. using `file://` URLs).
   *
   * * Example:
   * ```
   * // Unix
   * console.log(import.meta.dirname); // /home/alice
   *
   * // Windows
   * console.log(import.meta.dirname); // C:\alice
   * ```
   */
  dirname?: string;

  /** A flag that indicates if the current module is the main module that was
   * called when starting the program under Deno.
   *
   * ```ts
   * if (import.meta.main) {
   *   // this was loaded as the main module, maybe do some bootstrapping
   * }
   * ```
   */
  main: boolean;

  /** A function that returns resolved specifier as if it would be imported
   * using `import(specifier)`.
   *
   * ```ts
   * console.log(import.meta.resolve("./foo.js"));
   * // file:///dev/foo.js
   * ```
   */
  resolve(specifier: string): string;
}

/** Deno supports [User Timing Level 3](https://w3c.github.io/user-timing)
 * which is not widely supported yet in other runtimes.
 *
 * Check out the
 * [Performance API](https://developer.mozilla.org/en-US/docs/Web/API/Performance)
 * documentation on MDN for further information about how to use the API.
 *
 * @category Performance
 */
declare interface Performance {
  /** Stores a timestamp with the associated name (a "mark"). */
  mark(markName: string, options?: PerformanceMarkOptions): PerformanceMark;

  /** Stores the `DOMHighResTimeStamp` duration between two marks along with the
   * associated name (a "measure"). */
  measure(
    measureName: string,
    options?: PerformanceMeasureOptions,
  ): PerformanceMeasure;
}

/**
 * Options which are used in conjunction with `performance.mark`. Check out the
 * MDN
 * [`performance.mark()`](https://developer.mozilla.org/en-US/docs/Web/API/Performance/mark#markoptions)
 * documentation for more details.
 *
 * @category Performance
 */
declare interface PerformanceMarkOptions {
  /** Metadata to be included in the mark. */
  // deno-lint-ignore no-explicit-any
  detail?: any;

  /** Timestamp to be used as the mark time. */
  startTime?: number;
}

/**
 * Options which are used in conjunction with `performance.measure`. Check out the
 * MDN
 * [`performance.mark()`](https://developer.mozilla.org/en-US/docs/Web/API/Performance/measure#measureoptions)
 * documentation for more details.
 *
 * @category Performance
 */
declare interface PerformanceMeasureOptions {
  /** Metadata to be included in the measure. */
  // deno-lint-ignore no-explicit-any
  detail?: any;

  /** Timestamp to be used as the start time or string to be used as start
   * mark. */
  start?: string | number;

  /** Duration between the start and end times. */
  duration?: number;

  /** Timestamp to be used as the end time or string to be used as end mark. */
  end?: string | number;
}

/** The global namespace where Deno specific, non-standard APIs are located. */
declare namespace Deno {
  /** A set of error constructors that are raised by Deno APIs.
   *
   * Can be used to provide more specific handling of failures within code
   * which is using Deno APIs. For example, handling attempting to open a file
   * which does not exist:
   *
   * ```ts
   * try {
   *   const file = await Deno.open("./some/file.txt");
   * } catch (error) {
   *   if (error instanceof Deno.errors.NotFound) {
   *     console.error("the file was not found");
   *   } else {
   *     // otherwise re-throw
   *     throw error;
   *   }
   * }
   * ```
   *
   * @category Errors
   */
  export namespace errors {
    /**
     * Raised when the underlying operating system indicates that the file
     * was not found.
     *
     * @category Errors */
    export class NotFound extends Error {}
    /**
     * Raised when the underlying operating system indicates the current user
     * which the Deno process is running under does not have the appropriate
     * permissions to a file or resource.
     *
     * Before Deno 2.0, this error was raised when the user _did not_ provide
     * required `--allow-*` flag. As of Deno 2.0, that case is now handled by
     * the {@link NotCapable} error.
     *
     * @category Errors */
    export class PermissionDenied extends Error {}
    /**
     * Raised when the underlying operating system reports that a connection to
     * a resource is refused.
     *
     * @category Errors */
    export class ConnectionRefused extends Error {}
    /**
     * Raised when the underlying operating system reports that a connection has
     * been reset. With network servers, it can be a _normal_ occurrence where a
     * client will abort a connection instead of properly shutting it down.
     *
     * @category Errors */
    export class ConnectionReset extends Error {}
    /**
     * Raised when the underlying operating system reports an `ECONNABORTED`
     * error.
     *
     * @category Errors */
    export class ConnectionAborted extends Error {}
    /**
     * Raised when the underlying operating system reports an `ENOTCONN` error.
     *
     * @category Errors */
    export class NotConnected extends Error {}
    /**
     * Raised when attempting to open a server listener on an address and port
     * that already has a listener.
     *
     * @category Errors */
    export class AddrInUse extends Error {}
    /**
     * Raised when the underlying operating system reports an `EADDRNOTAVAIL`
     * error.
     *
     * @category Errors */
    export class AddrNotAvailable extends Error {}
    /**
     * Raised when trying to write to a resource and a broken pipe error occurs.
     * This can happen when trying to write directly to `stdout` or `stderr`
     * and the operating system is unable to pipe the output for a reason
     * external to the Deno runtime.
     *
     * @category Errors */
    export class BrokenPipe extends Error {}
    /**
     * Raised when trying to create a resource, like a file, that already
     * exits.
     *
     * @category Errors */
    export class AlreadyExists extends Error {}
    /**
     * Raised when an operation to returns data that is invalid for the
     * operation being performed.
     *
     * @category Errors */
    export class InvalidData extends Error {}
    /**
     * Raised when the underlying operating system reports that an I/O operation
     * has timed out (`ETIMEDOUT`).
     *
     * @category Errors */
    export class TimedOut extends Error {}
    /**
     * Raised when the underlying operating system reports an `EINTR` error. In
     * many cases, this underlying IO error will be handled internally within
     * Deno, or result in an @{link BadResource} error instead.
     *
     * @category Errors */
    export class Interrupted extends Error {}
    /**
     * Raised when the underlying operating system would need to block to
     * complete but an asynchronous (non-blocking) API is used.
     *
     * @category Errors */
    export class WouldBlock extends Error {}
    /**
     * Raised when expecting to write to a IO buffer resulted in zero bytes
     * being written.
     *
     * @category Errors */
    export class WriteZero extends Error {}
    /**
     * Raised when attempting to read bytes from a resource, but the EOF was
     * unexpectedly encountered.
     *
     * @category Errors */
    export class UnexpectedEof extends Error {}
    /**
     * The underlying IO resource is invalid or closed, and so the operation
     * could not be performed.
     *
     * @category Errors */
    export class BadResource extends Error {}
    /**
     * Raised in situations where when attempting to load a dynamic import,
     * too many redirects were encountered.
     *
     * @category Errors */
    export class Http extends Error {}
    /**
     * Raised when the underlying IO resource is not available because it is
     * being awaited on in another block of code.
     *
     * @category Errors */
    export class Busy extends Error {}
    /**
     * Raised when the underlying Deno API is asked to perform a function that
     * is not currently supported.
     *
     * @category Errors */
    export class NotSupported extends Error {}
    /**
     * Raised when too many symbolic links were encountered when resolving the
     * filename.
     *
     * @category Errors */
    export class FilesystemLoop extends Error {}
    /**
     * Raised when trying to open, create or write to a directory.
     *
     * @category Errors */
    export class IsADirectory extends Error {}
    /**
     * Raised when performing a socket operation but the remote host is
     * not reachable.
     *
     * @category Errors */
    export class NetworkUnreachable extends Error {}
    /**
     * Raised when trying to perform an operation on a path that is not a
     * directory, when directory is required.
     *
     * @category Errors */
    export class NotADirectory extends Error {}
    /**
     * Raised when trying to perform an operation while the relevant Deno
     * permission (like `--allow-read`) has not been granted.
     *
     * Before Deno 2.0, this condition was covered by the {@link PermissionDenied}
     * error.
     *
     * @category Errors */
    export class NotCapable extends Error {}
  }

  /** The current process ID of this instance of the Deno CLI.
   *
   * ```ts
   * console.log(Deno.pid);
   * ```
   *
   * @category Runtime
   */
  export const pid: number;

  /**
   * The process ID of parent process of this instance of the Deno CLI.
   *
   * ```ts
   * console.log(Deno.ppid);
   * ```
   *
   * @category Runtime
   */
  export const ppid: number;

  /** @category Runtime */
  export interface MemoryUsage {
    /** The number of bytes of the current Deno's process resident set size,
     * which is the amount of memory occupied in main memory (RAM). */
    rss: number;
    /** The total size of the heap for V8, in bytes. */
    heapTotal: number;
    /** The amount of the heap used for V8, in bytes. */
    heapUsed: number;
    /** Memory, in bytes, associated with JavaScript objects outside of the
     * JavaScript isolate. */
    external: number;
  }

  /**
   * Returns an object describing the memory usage of the Deno process and the
   * V8 subsystem measured in bytes.
   *
   * @category Runtime
   */
  export function memoryUsage(): MemoryUsage;

  /**
   * Get the `hostname` of the machine the Deno process is running on.
   *
   * ```ts
   * console.log(Deno.hostname());
   * ```
   *
   * Requires `allow-sys` permission.
   *
   * @tags allow-sys
   * @category Runtime
   */
  export function hostname(): string;

  /**
   * Returns an array containing the 1, 5, and 15 minute load averages. The
   * load average is a measure of CPU and IO utilization of the last one, five,
   * and 15 minute periods expressed as a fractional number.  Zero means there
   * is no load. On Windows, the three values are always the same and represent
   * the current load, not the 1, 5 and 15 minute load averages.
   *
   * ```ts
   * console.log(Deno.loadavg());  // e.g. [ 0.71, 0.44, 0.44 ]
   * ```
   *
   * Requires `allow-sys` permission.
   *
   * On Windows there is no API available to retrieve this information and this method returns `[ 0, 0, 0 ]`.
   *
   * @tags allow-sys
   * @category Runtime
   */
  export function loadavg(): number[];

  /**
   * The information for a network interface returned from a call to
   * {@linkcode Deno.networkInterfaces}.
   *
   * @category Network
   */
  export interface NetworkInterfaceInfo {
    /** The network interface name. */
    name: string;
    /** The IP protocol version. */
    family: "IPv4" | "IPv6";
    /** The IP address bound to the interface. */
    address: string;
    /** The netmask applied to the interface. */
    netmask: string;
    /** The IPv6 scope id or `null`. */
    scopeid: number | null;
    /** The CIDR range. */
    cidr: string;
    /** The MAC address. */
    mac: string;
  }

  /**
   * Returns an array of the network interface information.
   *
   * ```ts
   * console.log(Deno.networkInterfaces());
   * ```
   *
   * Requires `allow-sys` permission.
   *
   * @tags allow-sys
   * @category Network
   */
  export function networkInterfaces(): NetworkInterfaceInfo[];

  /**
   * Displays the total amount of free and used physical and swap memory in the
   * system, as well as the buffers and caches used by the kernel.
   *
   * This is similar to the `free` command in Linux
   *
   * ```ts
   * console.log(Deno.systemMemoryInfo());
   * ```
   *
   * Requires `allow-sys` permission.
   *
   * @tags allow-sys
   * @category Runtime
   */
  export function systemMemoryInfo(): SystemMemoryInfo;

  /**
   * Information returned from a call to {@linkcode Deno.systemMemoryInfo}.
   *
   * @category Runtime
   */
  export interface SystemMemoryInfo {
    /** Total installed memory in bytes. */
    total: number;
    /** Unused memory in bytes. */
    free: number;
    /** Estimation of how much memory, in bytes, is available for starting new
     * applications, without swapping. Unlike the data provided by the cache or
     * free fields, this field takes into account page cache and also that not
     * all reclaimable memory will be reclaimed due to items being in use.
     */
    available: number;
    /** Memory used by kernel buffers. */
    buffers: number;
    /** Memory used by the page cache and slabs. */
    cached: number;
    /** Total swap memory. */
    swapTotal: number;
    /** Unused swap memory. */
    swapFree: number;
  }

  /** Reflects the `NO_COLOR` environment variable at program start.
   *
   * When the value is `true`, the Deno CLI will attempt to not send color codes
   * to `stderr` or `stdout` and other command line programs should also attempt
   * to respect this value.
   *
   * See: https://no-color.org/
   *
   * @category Runtime
   */
  export const noColor: boolean;

  /**
   * Returns the release version of the Operating System.
   *
   * ```ts
   * console.log(Deno.osRelease());
   * ```
   *
   * Requires `allow-sys` permission.
   * Under consideration to possibly move to Deno.build or Deno.versions and if
   * it should depend sys-info, which may not be desirable.
   *
   * @tags allow-sys
   * @category Runtime
   */
  export function osRelease(): string;

  /**
   * Returns the Operating System uptime in number of seconds.
   *
   * ```ts
   * console.log(Deno.osUptime());
   * ```
   *
   * Requires `allow-sys` permission.
   *
   * @tags allow-sys
   * @category Runtime
   */
  export function osUptime(): number;

  /**
   * Options which define the permissions within a test or worker context.
   *
   * `"inherit"` ensures that all permissions of the parent process will be
   * applied to the test context. `"none"` ensures the test context has no
   * permissions. A `PermissionOptionsObject` provides a more specific
   * set of permissions to the test context.
   *
   * @category Permissions */
  export type PermissionOptions =
    | "inherit"
    | "none"
    | PermissionOptionsObject;

  /**
   * A set of options which can define the permissions within a test or worker
   * context at a highly specific level.
   *
   * @category Permissions */
  export interface PermissionOptionsObject {
    /** Specifies if the `env` permission should be requested or revoked.
     * If set to `"inherit"`, the current `env` permission will be inherited.
     * If set to `true`, the global `env` permission will be requested.
     * If set to `false`, the global `env` permission will be revoked.
     *
     * @default {false}
     */
    env?: "inherit" | boolean | string[];

    /** Specifies if the `sys` permission should be requested or revoked.
     * If set to `"inherit"`, the current `sys` permission will be inherited.
     * If set to `true`, the global `sys` permission will be requested.
     * If set to `false`, the global `sys` permission will be revoked.
     *
     * @default {false}
     */
    sys?: "inherit" | boolean | string[];

    /** Specifies if the `net` permission should be requested or revoked.
     * if set to `"inherit"`, the current `net` permission will be inherited.
     * if set to `true`, the global `net` permission will be requested.
     * if set to `false`, the global `net` permission will be revoked.
     * if set to `string[]`, the `net` permission will be requested with the
     * specified host strings with the format `"<host>[:<port>]`.
     *
     * @default {false}
     *
     * Examples:
     *
     * ```ts
     * import { assertEquals } from "jsr:@std/assert";
     *
     * Deno.test({
     *   name: "inherit",
     *   permissions: {
     *     net: "inherit",
     *   },
     *   async fn() {
     *     const status = await Deno.permissions.query({ name: "net" })
     *     assertEquals(status.state, "granted");
     *   },
     * });
     * ```
     *
     * ```ts
     * import { assertEquals } from "jsr:@std/assert";
     *
     * Deno.test({
     *   name: "true",
     *   permissions: {
     *     net: true,
     *   },
     *   async fn() {
     *     const status = await Deno.permissions.query({ name: "net" });
     *     assertEquals(status.state, "granted");
     *   },
     * });
     * ```
     *
     * ```ts
     * import { assertEquals } from "jsr:@std/assert";
     *
     * Deno.test({
     *   name: "false",
     *   permissions: {
     *     net: false,
     *   },
     *   async fn() {
     *     const status = await Deno.permissions.query({ name: "net" });
     *     assertEquals(status.state, "denied");
     *   },
     * });
     * ```
     *
     * ```ts
     * import { assertEquals } from "jsr:@std/assert";
     *
     * Deno.test({
     *   name: "localhost:8080",
     *   permissions: {
     *     net: ["localhost:8080"],
     *   },
     *   async fn() {
     *     const status = await Deno.permissions.query({ name: "net", host: "localhost:8080" });
     *     assertEquals(status.state, "granted");
     *   },
     * });
     * ```
     */
    net?: "inherit" | boolean | string[];

    /** Specifies if the `ffi` permission should be requested or revoked.
     * If set to `"inherit"`, the current `ffi` permission will be inherited.
     * If set to `true`, the global `ffi` permission will be requested.
     * If set to `false`, the global `ffi` permission will be revoked.
     *
     * @default {false}
     */
    ffi?: "inherit" | boolean | Array<string | URL>;

    /** Specifies if the `read` permission should be requested or revoked.
     * If set to `"inherit"`, the current `read` permission will be inherited.
     * If set to `true`, the global `read` permission will be requested.
     * If set to `false`, the global `read` permission will be revoked.
     * If set to `Array<string | URL>`, the `read` permission will be requested with the
     * specified file paths.
     *
     * @default {false}
     */
    read?: "inherit" | boolean | Array<string | URL>;

    /** Specifies if the `run` permission should be requested or revoked.
     * If set to `"inherit"`, the current `run` permission will be inherited.
     * If set to `true`, the global `run` permission will be requested.
     * If set to `false`, the global `run` permission will be revoked.
     *
     * @default {false}
     */
    run?: "inherit" | boolean | Array<string | URL>;

    /** Specifies if the `write` permission should be requested or revoked.
     * If set to `"inherit"`, the current `write` permission will be inherited.
     * If set to `true`, the global `write` permission will be requested.
     * If set to `false`, the global `write` permission will be revoked.
     * If set to `Array<string | URL>`, the `write` permission will be requested with the
     * specified file paths.
     *
     * @default {false}
     */
    write?: "inherit" | boolean | Array<string | URL>;
  }

  /**
   * Context that is passed to a testing function, which can be used to either
   * gain information about the current test, or register additional test
   * steps within the current test.
   *
   * @category Testing */
  export interface TestContext {
    /** The current test name. */
    name: string;
    /** The string URL of the current test. */
    origin: string;
    /** If the current test is a step of another test, the parent test context
     * will be set here. */
    parent?: TestContext;

    /** Run a sub step of the parent test or step. Returns a promise
     * that resolves to a boolean signifying if the step completed successfully.
     *
     * The returned promise never rejects unless the arguments are invalid.
     *
     * If the test was ignored the promise returns `false`.
     *
     * ```ts
     * Deno.test({
     *   name: "a parent test",
     *   async fn(t) {
     *     console.log("before the step");
     *     await t.step({
     *       name: "step 1",
     *       fn(t) {
     *         console.log("current step:", t.name);
     *       }
     *     });
     *     console.log("after the step");
     *   }
     * });
     * ```
     */
    step(definition: TestStepDefinition): Promise<boolean>;

    /** Run a sub step of the parent test or step. Returns a promise
     * that resolves to a boolean signifying if the step completed successfully.
     *
     * The returned promise never rejects unless the arguments are invalid.
     *
     * If the test was ignored the promise returns `false`.
     *
     * ```ts
     * Deno.test(
     *   "a parent test",
     *   async (t) => {
     *     console.log("before the step");
     *     await t.step(
     *       "step 1",
     *       (t) => {
     *         console.log("current step:", t.name);
     *       }
     *     );
     *     console.log("after the step");
     *   }
     * );
     * ```
     */
    step(
      name: string,
      fn: (t: TestContext) => void | Promise<void>,
    ): Promise<boolean>;

    /** Run a sub step of the parent test or step. Returns a promise
     * that resolves to a boolean signifying if the step completed successfully.
     *
     * The returned promise never rejects unless the arguments are invalid.
     *
     * If the test was ignored the promise returns `false`.
     *
     * ```ts
     * Deno.test(async function aParentTest(t) {
     *   console.log("before the step");
     *   await t.step(function step1(t) {
     *     console.log("current step:", t.name);
     *   });
     *   console.log("after the step");
     * });
     * ```
     */
    step(fn: (t: TestContext) => void | Promise<void>): Promise<boolean>;
  }

  /** @category Testing */
  export interface TestStepDefinition {
    /** The test function that will be tested when this step is executed. The
     * function can take an argument which will provide information about the
     * current step's context. */
    fn: (t: TestContext) => void | Promise<void>;
    /** The name of the step. */
    name: string;
    /** If truthy the current test step will be ignored.
     *
     * This is a quick way to skip over a step, but also can be used for
     * conditional logic, like determining if an environment feature is present.
     */
    ignore?: boolean;
    /** Check that the number of async completed operations after the test step
     * is the same as number of dispatched operations. This ensures that the
     * code tested does not start async operations which it then does
     * not await. This helps in preventing logic errors and memory leaks
     * in the application code.
     *
     * Defaults to the parent test or step's value. */
    sanitizeOps?: boolean;
    /** Ensure the test step does not "leak" resources - like open files or
     * network connections - by ensuring the open resources at the start of the
     * step match the open resources at the end of the step.
     *
     * Defaults to the parent test or step's value. */
    sanitizeResources?: boolean;
    /** Ensure the test step does not prematurely cause the process to exit,
     * for example via a call to {@linkcode Deno.exit}.
     *
     * Defaults to the parent test or step's value. */
    sanitizeExit?: boolean;
  }

  /** @category Testing */
  export interface TestDefinition {
    fn: (t: TestContext) => void | Promise<void>;
    /** The name of the test. */
    name: string;
    /** If truthy the current test step will be ignored.
     *
     * It is a quick way to skip over a step, but also can be used for
     * conditional logic, like determining if an environment feature is present.
     */
    ignore?: boolean;
    /** If at least one test has `only` set to `true`, only run tests that have
     * `only` set to `true` and fail the test suite. */
    only?: boolean;
    /** Check that the number of async completed operations after the test step
     * is the same as number of dispatched operations. This ensures that the
     * code tested does not start async operations which it then does
     * not await. This helps in preventing logic errors and memory leaks
     * in the application code.
     *
     * @default {true} */
    sanitizeOps?: boolean;
    /** Ensure the test step does not "leak" resources - like open files or
     * network connections - by ensuring the open resources at the start of the
     * test match the open resources at the end of the test.
     *
     * @default {true} */
    sanitizeResources?: boolean;
    /** Ensure the test case does not prematurely cause the process to exit,
     * for example via a call to {@linkcode Deno.exit}.
     *
     * @default {true} */
    sanitizeExit?: boolean;
    /** Specifies the permissions that should be used to run the test.
     *
     * Set this to "inherit" to keep the calling runtime permissions, set this
     * to "none" to revoke all permissions, or set a more specific set of
     * permissions using a {@linkcode PermissionOptionsObject}.
     *
     * @default {"inherit"} */
    permissions?: PermissionOptions;
  }

  /** Register a test which will be run when `deno test` is used on the command
   * line and the containing module looks like a test module.
   *
   * `fn` can be async if required.
   *
   * ```ts
   * import { assertEquals } from "jsr:@std/assert";
   *
   * Deno.test({
   *   name: "example test",
   *   fn() {
   *     assertEquals("world", "world");
   *   },
   * });
   *
   * Deno.test({
   *   name: "example ignored test",
   *   ignore: Deno.build.os === "windows",
   *   fn() {
   *     // This test is ignored only on Windows machines
   *   },
   * });
   *
   * Deno.test({
   *   name: "example async test",
   *   async fn() {
   *     const decoder = new TextDecoder("utf-8");
   *     const data = await Deno.readFile("hello_world.txt");
   *     assertEquals(decoder.decode(data), "Hello world");
   *   }
   * });
   * ```
   *
   * @category Testing
   */
  export const test: DenoTest;

  /**
   * @category Testing
   */
  export interface DenoTest {
    /** Register a test which will be run when `deno test` is used on the command
     * line and the containing module looks like a test module.
     *
     * `fn` can be async if required.
     *
     * ```ts
     * import { assertEquals } from "jsr:@std/assert";
     *
     * Deno.test({
     *   name: "example test",
     *   fn() {
     *     assertEquals("world", "world");
     *   },
     * });
     *
     * Deno.test({
     *   name: "example ignored test",
     *   ignore: Deno.build.os === "windows",
     *   fn() {
     *     // This test is ignored only on Windows machines
     *   },
     * });
     *
     * Deno.test({
     *   name: "example async test",
     *   async fn() {
     *     const decoder = new TextDecoder("utf-8");
     *     const data = await Deno.readFile("hello_world.txt");
     *     assertEquals(decoder.decode(data), "Hello world");
     *   }
     * });
     * ```
     *
     * @category Testing
     */
    (t: TestDefinition): void;

    /** Register a test which will be run when `deno test` is used on the command
     * line and the containing module looks like a test module.
     *
     * `fn` can be async if required.
     *
     * ```ts
     * import { assertEquals } from "jsr:@std/assert";
     *
     * Deno.test("My test description", () => {
     *   assertEquals("hello", "hello");
     * });
     *
     * Deno.test("My async test description", async () => {
     *   const decoder = new TextDecoder("utf-8");
     *   const data = await Deno.readFile("hello_world.txt");
     *   assertEquals(decoder.decode(data), "Hello world");
     * });
     * ```
     *
     * @category Testing
     */
    (
      name: string,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Register a test which will be run when `deno test` is used on the command
     * line and the containing module looks like a test module.
     *
     * `fn` can be async if required. Declared function must have a name.
     *
     * ```ts
     * import { assertEquals } from "jsr:@std/assert";
     *
     * Deno.test(function myTestName() {
     *   assertEquals("hello", "hello");
     * });
     *
     * Deno.test(async function myOtherTestName() {
     *   const decoder = new TextDecoder("utf-8");
     *   const data = await Deno.readFile("hello_world.txt");
     *   assertEquals(decoder.decode(data), "Hello world");
     * });
     * ```
     *
     * @category Testing
     */
    (fn: (t: TestContext) => void | Promise<void>): void;

    /** Register a test which will be run when `deno test` is used on the command
     * line and the containing module looks like a test module.
     *
     * `fn` can be async if required.
     *
     * ```ts
     * import { assert, fail, assertEquals } from "jsr:@std/assert";
     *
     * Deno.test("My test description", { permissions: { read: true } }, (): void => {
     *   assertEquals("hello", "hello");
     * });
     *
     * Deno.test("My async test description", { permissions: { read: false } }, async (): Promise<void> => {
     *   const decoder = new TextDecoder("utf-8");
     *   const data = await Deno.readFile("hello_world.txt");
     *   assertEquals(decoder.decode(data), "Hello world");
     * });
     * ```
     *
     * @category Testing
     */
    (
      name: string,
      options: Omit<TestDefinition, "fn" | "name">,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Register a test which will be run when `deno test` is used on the command
     * line and the containing module looks like a test module.
     *
     * `fn` can be async if required.
     *
     * ```ts
     * import { assertEquals } from "jsr:@std/assert";
     *
     * Deno.test(
     *   {
     *     name: "My test description",
     *     permissions: { read: true },
     *   },
     *   () => {
     *     assertEquals("hello", "hello");
     *   },
     * );
     *
     * Deno.test(
     *   {
     *     name: "My async test description",
     *     permissions: { read: false },
     *   },
     *   async () => {
     *     const decoder = new TextDecoder("utf-8");
     *     const data = await Deno.readFile("hello_world.txt");
     *     assertEquals(decoder.decode(data), "Hello world");
     *   },
     * );
     * ```
     *
     * @category Testing
     */
    (
      options: Omit<TestDefinition, "fn" | "name">,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Register a test which will be run when `deno test` is used on the command
     * line and the containing module looks like a test module.
     *
     * `fn` can be async if required. Declared function must have a name.
     *
     * ```ts
     * import { assertEquals } from "jsr:@std/assert";
     *
     * Deno.test(
     *   { permissions: { read: true } },
     *   function myTestName() {
     *     assertEquals("hello", "hello");
     *   },
     * );
     *
     * Deno.test(
     *   { permissions: { read: false } },
     *   async function myOtherTestName() {
     *     const decoder = new TextDecoder("utf-8");
     *     const data = await Deno.readFile("hello_world.txt");
     *     assertEquals(decoder.decode(data), "Hello world");
     *   },
     * );
     * ```
     *
     * @category Testing
     */
    (
      options: Omit<TestDefinition, "fn">,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Shorthand property for ignoring a particular test case.
     *
     * @category Testing
     */
    ignore(t: Omit<TestDefinition, "ignore">): void;

    /** Shorthand property for ignoring a particular test case.
     *
     * @category Testing
     */
    ignore(
      name: string,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Shorthand property for ignoring a particular test case.
     *
     * @category Testing
     */
    ignore(fn: (t: TestContext) => void | Promise<void>): void;

    /** Shorthand property for ignoring a particular test case.
     *
     * @category Testing
     */
    ignore(
      name: string,
      options: Omit<TestDefinition, "fn" | "name" | "ignore">,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Shorthand property for ignoring a particular test case.
     *
     * @category Testing
     */
    ignore(
      options: Omit<TestDefinition, "fn" | "name" | "ignore">,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Shorthand property for ignoring a particular test case.
     *
     * @category Testing
     */
    ignore(
      options: Omit<TestDefinition, "fn" | "ignore">,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Shorthand property for focusing a particular test case.
     *
     * @category Testing
     */
    only(t: Omit<TestDefinition, "only">): void;

    /** Shorthand property for focusing a particular test case.
     *
     * @category Testing
     */
    only(
      name: string,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Shorthand property for focusing a particular test case.
     *
     * @category Testing
     */
    only(fn: (t: TestContext) => void | Promise<void>): void;

    /** Shorthand property for focusing a particular test case.
     *
     * @category Testing
     */
    only(
      name: string,
      options: Omit<TestDefinition, "fn" | "name" | "only">,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Shorthand property for focusing a particular test case.
     *
     * @category Testing
     */
    only(
      options: Omit<TestDefinition, "fn" | "name" | "only">,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;

    /** Shorthand property for focusing a particular test case.
     *
     * @category Testing
     */
    only(
      options: Omit<TestDefinition, "fn" | "only">,
      fn: (t: TestContext) => void | Promise<void>,
    ): void;
  }

  /**
   * Context that is passed to a benchmarked function. The instance is shared
   * between iterations of the benchmark. Its methods can be used for example
   * to override of the measured portion of the function.
   *
   * @category Testing
   */
  export interface BenchContext {
    /** The current benchmark name. */
    name: string;
    /** The string URL of the current benchmark. */
    origin: string;

    /** Restarts the timer for the bench measurement. This should be called
     * after doing setup work which should not be measured.
     *
     * Warning: This method should not be used for benchmarks averaging less
     * than 10μs per iteration. In such cases it will be disabled but the call
     * will still have noticeable overhead, resulting in a warning.
     *
     * ```ts
     * Deno.bench("foo", async (t) => {
     *   const data = await Deno.readFile("data.txt");
     *   t.start();
     *   // some operation on `data`...
     * });
     * ```
     */
    start(): void;

    /** End the timer early for the bench measurement. This should be called
     * before doing teardown work which should not be measured.
     *
     * Warning: This method should not be used for benchmarks averaging less
     * than 10μs per iteration. In such cases it will be disabled but the call
     * will still have noticeable overhead, resulting in a warning.
     *
     * ```ts
     * Deno.bench("foo", async (t) => {
     *   using file = await Deno.open("data.txt");
     *   t.start();
     *   // some operation on `file`...
     *   t.end();
     * });
     * ```
     */
    end(): void;
  }

  /**
   * The interface for defining a benchmark test using {@linkcode Deno.bench}.
   *
   * @category Testing
   */
  export interface BenchDefinition {
    /** The test function which will be benchmarked. */
    fn: (b: BenchContext) => void | Promise<void>;
    /** The name of the test, which will be used in displaying the results. */
    name: string;
    /** If truthy, the benchmark test will be ignored/skipped. */
    ignore?: boolean;
    /** Group name for the benchmark.
     *
     * Grouped benchmarks produce a group time summary, where the difference
     * in performance between each test of the group is compared. */
    group?: string;
    /** Benchmark should be used as the baseline for other benchmarks.
     *
     * If there are multiple baselines in a group, the first one is used as the
     * baseline. */
    baseline?: boolean;
    /** If at least one bench has `only` set to true, only run benches that have
     * `only` set to `true` and fail the bench suite. */
    only?: boolean;
    /** Ensure the bench case does not prematurely cause the process to exit,
     * for example via a call to {@linkcode Deno.exit}.
     *
     * @default {true} */
    sanitizeExit?: boolean;
    /** Specifies the permissions that should be used to run the bench.
     *
     * Set this to `"inherit"` to keep the calling thread's permissions.
     *
     * Set this to `"none"` to revoke all permissions.
     *
     * @default {"inherit"}
     */
    permissions?: PermissionOptions;
  }

  /**
   * Register a benchmark test which will be run when `deno bench` is used on
   * the command line and the containing module looks like a bench module.
   *
   * If the test function (`fn`) returns a promise or is async, the test runner
   * will await resolution to consider the test complete.
   *
   * ```ts
   * import { assertEquals } from "jsr:@std/assert";
   *
   * Deno.bench({
   *   name: "example test",
   *   fn() {
   *     assertEquals("world", "world");
   *   },
   * });
   *
   * Deno.bench({
   *   name: "example ignored test",
   *   ignore: Deno.build.os === "windows",
   *   fn() {
   *     // This test is ignored only on Windows machines
   *   },
   * });
   *
   * Deno.bench({
   *   name: "example async test",
   *   async fn() {
   *     const decoder = new TextDecoder("utf-8");
   *     const data = await Deno.readFile("hello_world.txt");
   *     assertEquals(decoder.decode(data), "Hello world");
   *   }
   * });
   * ```
   *
   * @category Testing
   */
  export function bench(b: BenchDefinition): void;

  /**
   * Register a benchmark test which will be run when `deno bench` is used on
   * the command line and the containing module looks like a bench module.
   *
   * If the test function (`fn`) returns a promise or is async, the test runner
   * will await resolution to consider the test complete.
   *
   * ```ts
   * import { assertEquals } from "jsr:@std/assert";
   *
   * Deno.bench("My test description", () => {
   *   assertEquals("hello", "hello");
   * });
   *
   * Deno.bench("My async test description", async () => {
   *   const decoder = new TextDecoder("utf-8");
   *   const data = await Deno.readFile("hello_world.txt");
   *   assertEquals(decoder.decode(data), "Hello world");
   * });
   * ```
   *
   * @category Testing
   */
  export function bench(
    name: string,
    fn: (b: BenchContext) => void | Promise<void>,
  ): void;

  /**
   * Register a benchmark test which will be run when `deno bench` is used on
   * the command line and the containing module looks like a bench module.
   *
   * If the test function (`fn`) returns a promise or is async, the test runner
   * will await resolution to consider the test complete.
   *
   * ```ts
   * import { assertEquals } from "jsr:@std/assert";
   *
   * Deno.bench(function myTestName() {
   *   assertEquals("hello", "hello");
   * });
   *
   * Deno.bench(async function myOtherTestName() {
   *   const decoder = new TextDecoder("utf-8");
   *   const data = await Deno.readFile("hello_world.txt");
   *   assertEquals(decoder.decode(data), "Hello world");
   * });
   * ```
   *
   * @category Testing
   */
  export function bench(fn: (b: BenchContext) => void | Promise<void>): void;

  /**
   * Register a benchmark test which will be run when `deno bench` is used on
   * the command line and the containing module looks like a bench module.
   *
   * If the test function (`fn`) returns a promise or is async, the test runner
   * will await resolution to consider the test complete.
   *
   * ```ts
   * import { assertEquals } from "jsr:@std/assert";
   *
   * Deno.bench(
   *   "My test description",
   *   { permissions: { read: true } },
   *   () => {
   *    assertEquals("hello", "hello");
   *   }
   * );
   *
   * Deno.bench(
   *   "My async test description",
   *   { permissions: { read: false } },
   *   async () => {
   *     const decoder = new TextDecoder("utf-8");
   *     const data = await Deno.readFile("hello_world.txt");
   *     assertEquals(decoder.decode(data), "Hello world");
   *   }
   * );
   * ```
   *
   * @category Testing
   */
  export function bench(
    name: string,
    options: Omit<BenchDefinition, "fn" | "name">,
    fn: (b: BenchContext) => void | Promise<void>,
  ): void;

  /**
   * Register a benchmark test which will be run when `deno bench` is used on
   * the command line and the containing module looks like a bench module.
   *
   * If the test function (`fn`) returns a promise or is async, the test runner
   * will await resolution to consider the test complete.
   *
   * ```ts
   * import { assertEquals } from "jsr:@std/assert";
   *
   * Deno.bench(
   *   { name: "My test description", permissions: { read: true } },
   *   () => {
   *     assertEquals("hello", "hello");
   *   }
   * );
   *
   * Deno.bench(
   *   { name: "My async test description", permissions: { read: false } },
   *   async () => {
   *     const decoder = new TextDecoder("utf-8");
   *     const data = await Deno.readFile("hello_world.txt");
   *     assertEquals(decoder.decode(data), "Hello world");
   *   }
   * );
   * ```
   *
   * @category Testing
   */
  export function bench(
    options: Omit<BenchDefinition, "fn">,
    fn: (b: BenchContext) => void | Promise<void>,
  ): void;

  /**
   * Register a benchmark test which will be run when `deno bench` is used on
   * the command line and the containing module looks like a bench module.
   *
   * If the test function (`fn`) returns a promise or is async, the test runner
   * will await resolution to consider the test complete.
   *
   * ```ts
   * import { assertEquals } from "jsr:@std/assert";
   *
   * Deno.bench(
   *   { permissions: { read: true } },
   *   function myTestName() {
   *     assertEquals("hello", "hello");
   *   }
   * );
   *
   * Deno.bench(
   *   { permissions: { read: false } },
   *   async function myOtherTestName() {
   *     const decoder = new TextDecoder("utf-8");
   *     const data = await Deno.readFile("hello_world.txt");
   *     assertEquals(decoder.decode(data), "Hello world");
   *   }
   * );
   * ```
   *
   * @category Testing
   */
  export function bench(
    options: Omit<BenchDefinition, "fn" | "name">,
    fn: (b: BenchContext) => void | Promise<void>,
  ): void;

  /** Exit the Deno process with optional exit code.
   *
   * If no exit code is supplied then Deno will exit with return code of `0`.
   *
   * In worker contexts this is an alias to `self.close();`.
   *
   * ```ts
   * Deno.exit(5);
   * ```
   *
   * @category Runtime
   */
  export function exit(code?: number): never;

  /** The exit code for the Deno process.
   *
   * If no exit code has been supplied, then Deno will assume a return code of `0`.
   *
   * When setting an exit code value, a number or non-NaN string must be provided,
   * otherwise a TypeError will be thrown.
   *
   * ```ts
   * console.log(Deno.exitCode); //-> 0
   * Deno.exitCode = 1;
   * console.log(Deno.exitCode); //-> 1
   * ```
   *
   * @category Runtime
   */
  export var exitCode: number;

  /** An interface containing methods to interact with the process environment
   * variables.
   *
   * @tags allow-env
   * @category Runtime
   */
  export interface Env {
    /** Retrieve the value of an environment variable.
     *
     * Returns `undefined` if the supplied environment variable is not defined.
     *
     * ```ts
     * console.log(Deno.env.get("HOME"));  // e.g. outputs "/home/alice"
     * console.log(Deno.env.get("MADE_UP_VAR"));  // outputs "undefined"
     * ```
     *
     * Requires `allow-env` permission.
     *
     * @tags allow-env
     */
    get(key: string): string | undefined;

    /** Set the value of an environment variable.
     *
     * ```ts
     * Deno.env.set("SOME_VAR", "Value");
     * Deno.env.get("SOME_VAR");  // outputs "Value"
     * ```
     *
     * Requires `allow-env` permission.
     *
     * @tags allow-env
     */
    set(key: string, value: string): void;

    /** Delete the value of an environment variable.
     *
     * ```ts
     * Deno.env.set("SOME_VAR", "Value");
     * Deno.env.delete("SOME_VAR");  // outputs "undefined"
     * ```
     *
     * Requires `allow-env` permission.
     *
     * @tags allow-env
     */
    delete(key: string): void;

    /** Check whether an environment variable is present or not.
     *
     * ```ts
     * Deno.env.set("SOME_VAR", "Value");
     * Deno.env.has("SOME_VAR");  // outputs true
     * ```
     *
     * Requires `allow-env` permission.
     *
     * @tags allow-env
     */
    has(key: string): boolean;

    /** Returns a snapshot of the environment variables at invocation as a
     * simple object of keys and values.
     *
     * ```ts
     * Deno.env.set("TEST_VAR", "A");
     * const myEnv = Deno.env.toObject();
     * console.log(myEnv.SHELL);
     * Deno.env.set("TEST_VAR", "B");
     * console.log(myEnv.TEST_VAR);  // outputs "A"
     * ```
     *
     * Requires `allow-env` permission.
     *
     * @tags allow-env
     */
    toObject(): { [index: string]: string };
  }

  /** An interface containing methods to interact with the process environment
   * variables.
   *
   * @tags allow-env
   * @category Runtime
   */
  export const env: Env;

  /**
   * Returns the path to the current deno executable.
   *
   * ```ts
   * console.log(Deno.execPath());  // e.g. "/home/alice/.local/bin/deno"
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category Runtime
   */
  export function execPath(): string;

  /**
   * Change the current working directory to the specified path.
   *
   * ```ts
   * Deno.chdir("/home/userA");
   * Deno.chdir("../userB");
   * Deno.chdir("C:\\Program Files (x86)\\Java");
   * ```
   *
   * Throws {@linkcode Deno.errors.NotFound} if directory not found.
   *
   * Throws {@linkcode Deno.errors.PermissionDenied} if the user does not have
   * operating system file access rights.
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category Runtime
   */
  export function chdir(directory: string | URL): void;

  /**
   * Return a string representing the current working directory.
   *
   * If the current directory can be reached via multiple paths (due to symbolic
   * links), `cwd()` may return any one of them.
   *
   * ```ts
   * const currentWorkingDirectory = Deno.cwd();
   * ```
   *
   * Throws {@linkcode Deno.errors.NotFound} if directory not available.
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category Runtime
   */
  export function cwd(): string;

  /**
   * Creates `newpath` as a hard link to `oldpath`.
   *
   * ```ts
   * await Deno.link("old/name", "new/name");
   * ```
   *
   * Requires `allow-read` and `allow-write` permissions.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function link(oldpath: string, newpath: string): Promise<void>;

  /**
   * Synchronously creates `newpath` as a hard link to `oldpath`.
   *
   * ```ts
   * Deno.linkSync("old/name", "new/name");
   * ```
   *
   * Requires `allow-read` and `allow-write` permissions.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function linkSync(oldpath: string, newpath: string): void;

  /**
   * A enum which defines the seek mode for IO related APIs that support
   * seeking.
   *
   * @category I/O */
  export enum SeekMode {
    /* Seek from the start of the file/resource. */
    Start = 0,
    /* Seek from the current position within the file/resource. */
    Current = 1,
    /* Seek from the end of the current file/resource. */
    End = 2,
  }

  /**
   * An abstract interface which when implemented provides an interface to seek
   * within an open file/resource asynchronously.
   *
   * @category I/O */
  export interface Seeker {
    /** Seek sets the offset for the next `read()` or `write()` to offset,
     * interpreted according to `whence`: `Start` means relative to the
     * start of the file, `Current` means relative to the current offset,
     * and `End` means relative to the end. Seek resolves to the new offset
     * relative to the start of the file.
     *
     * Seeking to an offset before the start of the file is an error. Seeking to
     * any positive offset is legal, but the behavior of subsequent I/O
     * operations on the underlying object is implementation-dependent.
     *
     * It resolves with the updated offset.
     */
    seek(offset: number | bigint, whence: SeekMode): Promise<number>;
  }

  /**
   * An abstract interface which when implemented provides an interface to seek
   * within an open file/resource synchronously.
   *
   * @category I/O */
  export interface SeekerSync {
    /** Seek sets the offset for the next `readSync()` or `writeSync()` to
     * offset, interpreted according to `whence`: `Start` means relative
     * to the start of the file, `Current` means relative to the current
     * offset, and `End` means relative to the end.
     *
     * Seeking to an offset before the start of the file is an error. Seeking to
     * any positive offset is legal, but the behavior of subsequent I/O
     * operations on the underlying object is implementation-dependent.
     *
     * It returns the updated offset.
     */
    seekSync(offset: number | bigint, whence: SeekMode): number;
  }

  /** Open a file and resolve to an instance of {@linkcode Deno.FsFile}. The
   * file does not need to previously exist if using the `create` or `createNew`
   * open options. The caller may have the resulting file automatically closed
   * by the runtime once it's out of scope by declaring the file variable with
   * the `using` keyword.
   *
   * ```ts
   * using file = await Deno.open("/foo/bar.txt", { read: true, write: true });
   * // Do work with file
   * ```
   *
   * Alternatively, the caller may manually close the resource when finished with
   * it.
   *
   * ```ts
   * const file = await Deno.open("/foo/bar.txt", { read: true, write: true });
   * // Do work with file
   * file.close();
   * ```
   *
   * Requires `allow-read` and/or `allow-write` permissions depending on
   * options.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function open(
    path: string | URL,
    options?: OpenOptions,
  ): Promise<FsFile>;

  /** Synchronously open a file and return an instance of
   * {@linkcode Deno.FsFile}. The file does not need to previously exist if
   * using the `create` or `createNew` open options. The caller may have the
   * resulting file automatically closed by the runtime once it's out of scope
   * by declaring the file variable with the `using` keyword.
   *
   * ```ts
   * using file = Deno.openSync("/foo/bar.txt", { read: true, write: true });
   * // Do work with file
   * ```
   *
   * Alternatively, the caller may manually close the resource when finished with
   * it.
   *
   * ```ts
   * const file = Deno.openSync("/foo/bar.txt", { read: true, write: true });
   * // Do work with file
   * file.close();
   * ```
   *
   * Requires `allow-read` and/or `allow-write` permissions depending on
   * options.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function openSync(path: string | URL, options?: OpenOptions): FsFile;

  /** Creates a file if none exists or truncates an existing file and resolves to
   *  an instance of {@linkcode Deno.FsFile}.
   *
   * ```ts
   * const file = await Deno.create("/foo/bar.txt");
   * ```
   *
   * Requires `allow-read` and `allow-write` permissions.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function create(path: string | URL): Promise<FsFile>;

  /** Creates a file if none exists or truncates an existing file and returns
   *  an instance of {@linkcode Deno.FsFile}.
   *
   * ```ts
   * const file = Deno.createSync("/foo/bar.txt");
   * ```
   *
   * Requires `allow-read` and `allow-write` permissions.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function createSync(path: string | URL): FsFile;

  /** The Deno abstraction for reading and writing files.
   *
   * This is the most straight forward way of handling files within Deno and is
   * recommended over using the discrete functions within the `Deno` namespace.
   *
   * ```ts
   * using file = await Deno.open("/foo/bar.txt", { read: true });
   * const fileInfo = await file.stat();
   * if (fileInfo.isFile) {
   *   const buf = new Uint8Array(100);
   *   const numberOfBytesRead = await file.read(buf); // 11 bytes
   *   const text = new TextDecoder().decode(buf);  // "hello world"
   * }
   * ```
   *
   * @category File System
   */
  export class FsFile implements Seeker, SeekerSync, Disposable {
    /** A {@linkcode ReadableStream} instance representing to the byte contents
     * of the file. This makes it easy to interoperate with other web streams
     * based APIs.
     *
     * ```ts
     * using file = await Deno.open("my_file.txt", { read: true });
     * const decoder = new TextDecoder();
     * for await (const chunk of file.readable) {
     *   console.log(decoder.decode(chunk));
     * }
     * ```
     */
    readonly readable: ReadableStream<Uint8Array>;
    /** A {@linkcode WritableStream} instance to write the contents of the
     * file. This makes it easy to interoperate with other web streams based
     * APIs.
     *
     * ```ts
     * const items = ["hello", "world"];
     * using file = await Deno.open("my_file.txt", { write: true });
     * const encoder = new TextEncoder();
     * const writer = file.writable.getWriter();
     * for (const item of items) {
     *   await writer.write(encoder.encode(item));
     * }
     * ```
     */
    readonly writable: WritableStream<Uint8Array>;
    /** Write the contents of the array buffer (`p`) to the file.
     *
     * Resolves to the number of bytes written.
     *
     * **It is not guaranteed that the full buffer will be written in a single
     * call.**
     *
     * ```ts
     * const encoder = new TextEncoder();
     * const data = encoder.encode("Hello world");
     * using file = await Deno.open("/foo/bar.txt", { write: true });
     * const bytesWritten = await file.write(data); // 11
     * ```
     *
     * @category I/O
     */
    write(p: Uint8Array): Promise<number>;
    /** Synchronously write the contents of the array buffer (`p`) to the file.
     *
     * Returns the number of bytes written.
     *
     * **It is not guaranteed that the full buffer will be written in a single
     * call.**
     *
     * ```ts
     * const encoder = new TextEncoder();
     * const data = encoder.encode("Hello world");
     * using file = Deno.openSync("/foo/bar.txt", { write: true });
     * const bytesWritten = file.writeSync(data); // 11
     * ```
     */
    writeSync(p: Uint8Array): number;
    /** Truncates (or extends) the file to reach the specified `len`. If `len`
     * is not specified, then the entire file contents are truncated.
     *
     * ### Truncate the entire file
     *
     * ```ts
     * using file = await Deno.open("my_file.txt", { write: true });
     * await file.truncate();
     * ```
     *
     * ### Truncate part of the file
     *
     * ```ts
     * // if "my_file.txt" contains the text "hello world":
     * using file = await Deno.open("my_file.txt", { write: true });
     * await file.truncate(7);
     * const buf = new Uint8Array(100);
     * await file.read(buf);
     * const text = new TextDecoder().decode(buf); // "hello w"
     * ```
     */
    truncate(len?: number): Promise<void>;
    /** Synchronously truncates (or extends) the file to reach the specified
     * `len`. If `len` is not specified, then the entire file contents are
     * truncated.
     *
     * ### Truncate the entire file
     *
     * ```ts
     * using file = Deno.openSync("my_file.txt", { write: true });
     * file.truncateSync();
     * ```
     *
     * ### Truncate part of the file
     *
     * ```ts
     * // if "my_file.txt" contains the text "hello world":
     * using file = Deno.openSync("my_file.txt", { write: true });
     * file.truncateSync(7);
     * const buf = new Uint8Array(100);
     * file.readSync(buf);
     * const text = new TextDecoder().decode(buf); // "hello w"
     * ```
     */
    truncateSync(len?: number): void;
    /** Read the file into an array buffer (`p`).
     *
     * Resolves to either the number of bytes read during the operation or EOF
     * (`null`) if there was nothing more to read.
     *
     * It is possible for a read to successfully return with `0` bytes. This
     * does not indicate EOF.
     *
     * **It is not guaranteed that the full buffer will be read in a single
     * call.**
     *
     * ```ts
     * // if "/foo/bar.txt" contains the text "hello world":
     * using file = await Deno.open("/foo/bar.txt");
     * const buf = new Uint8Array(100);
     * const numberOfBytesRead = await file.read(buf); // 11 bytes
     * const text = new TextDecoder().decode(buf);  // "hello world"
     * ```
     */
    read(p: Uint8Array): Promise<number | null>;
    /** Synchronously read from the file into an array buffer (`p`).
     *
     * Returns either the number of bytes read during the operation or EOF
     * (`null`) if there was nothing more to read.
     *
     * It is possible for a read to successfully return with `0` bytes. This
     * does not indicate EOF.
     *
     * **It is not guaranteed that the full buffer will be read in a single
     * call.**
     *
     * ```ts
     * // if "/foo/bar.txt" contains the text "hello world":
     * using file = Deno.openSync("/foo/bar.txt");
     * const buf = new Uint8Array(100);
     * const numberOfBytesRead = file.readSync(buf); // 11 bytes
     * const text = new TextDecoder().decode(buf);  // "hello world"
     * ```
     */
    readSync(p: Uint8Array): number | null;
    /** Seek to the given `offset` under mode given by `whence`. The call
     * resolves to the new position within the resource (bytes from the start).
     *
     * ```ts
     * // Given the file contains "Hello world" text, which is 11 bytes long:
     * using file = await Deno.open(
     *   "hello.txt",
     *   { read: true, write: true, truncate: true, create: true },
     * );
     * await file.write(new TextEncoder().encode("Hello world"));
     *
     * // advance cursor 6 bytes
     * const cursorPosition = await file.seek(6, Deno.SeekMode.Start);
     * console.log(cursorPosition);  // 6
     * const buf = new Uint8Array(100);
     * await file.read(buf);
     * console.log(new TextDecoder().decode(buf)); // "world"
     * ```
     *
     * The seek modes work as follows:
     *
     * ```ts
     * // Given the file contains "Hello world" text, which is 11 bytes long:
     * const file = await Deno.open(
     *   "hello.txt",
     *   { read: true, write: true, truncate: true, create: true },
     * );
     * await file.write(new TextEncoder().encode("Hello world"));
     *
     * // Seek 6 bytes from the start of the file
     * console.log(await file.seek(6, Deno.SeekMode.Start)); // "6"
     * // Seek 2 more bytes from the current position
     * console.log(await file.seek(2, Deno.SeekMode.Current)); // "8"
     * // Seek backwards 2 bytes from the end of the file
     * console.log(await file.seek(-2, Deno.SeekMode.End)); // "9" (i.e. 11-2)
     * ```
     */
    seek(offset: number | bigint, whence: SeekMode): Promise<number>;
    /** Synchronously seek to the given `offset` under mode given by `whence`.
     * The new position within the resource (bytes from the start) is returned.
     *
     * ```ts
     * using file = Deno.openSync(
     *   "hello.txt",
     *   { read: true, write: true, truncate: true, create: true },
     * );
     * file.writeSync(new TextEncoder().encode("Hello world"));
     *
     * // advance cursor 6 bytes
     * const cursorPosition = file.seekSync(6, Deno.SeekMode.Start);
     * console.log(cursorPosition);  // 6
     * const buf = new Uint8Array(100);
     * file.readSync(buf);
     * console.log(new TextDecoder().decode(buf)); // "world"
     * ```
     *
     * The seek modes work as follows:
     *
     * ```ts
     * // Given the file contains "Hello world" text, which is 11 bytes long:
     * using file = Deno.openSync(
     *   "hello.txt",
     *   { read: true, write: true, truncate: true, create: true },
     * );
     * file.writeSync(new TextEncoder().encode("Hello world"));
     *
     * // Seek 6 bytes from the start of the file
     * console.log(file.seekSync(6, Deno.SeekMode.Start)); // "6"
     * // Seek 2 more bytes from the current position
     * console.log(file.seekSync(2, Deno.SeekMode.Current)); // "8"
     * // Seek backwards 2 bytes from the end of the file
     * console.log(file.seekSync(-2, Deno.SeekMode.End)); // "9" (i.e. 11-2)
     * ```
     */
    seekSync(offset: number | bigint, whence: SeekMode): number;
    /** Resolves to a {@linkcode Deno.FileInfo} for the file.
     *
     * ```ts
     * import { assert } from "jsr:@std/assert";
     *
     * using file = await Deno.open("hello.txt");
     * const fileInfo = await file.stat();
     * assert(fileInfo.isFile);
     * ```
     */
    stat(): Promise<FileInfo>;
    /** Synchronously returns a {@linkcode Deno.FileInfo} for the file.
     *
     * ```ts
     * import { assert } from "jsr:@std/assert";
     *
     * using file = Deno.openSync("hello.txt")
     * const fileInfo = file.statSync();
     * assert(fileInfo.isFile);
     * ```
     */
    statSync(): FileInfo;
    /**
     * Flushes any pending data and metadata operations of the given file
     * stream to disk.
     *
     * ```ts
     * const file = await Deno.open(
     *   "my_file.txt",
     *   { read: true, write: true, create: true },
     * );
     * await file.write(new TextEncoder().encode("Hello World"));
     * await file.truncate(1);
     * await file.sync();
     * console.log(await Deno.readTextFile("my_file.txt")); // H
     * ```
     *
     * @category I/O
     */
    sync(): Promise<void>;
    /**
     * Synchronously flushes any pending data and metadata operations of the given
     * file stream to disk.
     *
     * ```ts
     * const file = Deno.openSync(
     *   "my_file.txt",
     *   { read: true, write: true, create: true },
     * );
     * file.writeSync(new TextEncoder().encode("Hello World"));
     * file.truncateSync(1);
     * file.syncSync();
     * console.log(Deno.readTextFileSync("my_file.txt")); // H
     * ```
     *
     * @category I/O
     */
    syncSync(): void;
    /**
     * Flushes any pending data operations of the given file stream to disk.
     *  ```ts
     * using file = await Deno.open(
     *   "my_file.txt",
     *   { read: true, write: true, create: true },
     * );
     * await file.write(new TextEncoder().encode("Hello World"));
     * await file.syncData();
     * console.log(await Deno.readTextFile("my_file.txt")); // Hello World
     * ```
     *
     * @category I/O
     */
    syncData(): Promise<void>;
    /**
     * Synchronously flushes any pending data operations of the given file stream
     * to disk.
     *
     *  ```ts
     * using file = Deno.openSync(
     *   "my_file.txt",
     *   { read: true, write: true, create: true },
     * );
     * file.writeSync(new TextEncoder().encode("Hello World"));
     * file.syncDataSync();
     * console.log(Deno.readTextFileSync("my_file.txt")); // Hello World
     * ```
     *
     * @category I/O
     */
    syncDataSync(): void;
    /**
     * Changes the access (`atime`) and modification (`mtime`) times of the
     * file stream resource. Given times are either in seconds (UNIX epoch
     * time) or as `Date` objects.
     *
     * ```ts
     * using file = await Deno.open("file.txt", { create: true, write: true });
     * await file.utime(1556495550, new Date());
     * ```
     *
     * @category File System
     */
    utime(atime: number | Date, mtime: number | Date): Promise<void>;
    /**
     * Synchronously changes the access (`atime`) and modification (`mtime`)
     * times of the file stream resource. Given times are either in seconds
     * (UNIX epoch time) or as `Date` objects.
     *
     * ```ts
     * using file = Deno.openSync("file.txt", { create: true, write: true });
     * file.utime(1556495550, new Date());
     * ```
     *
     * @category File System
     */
    utimeSync(atime: number | Date, mtime: number | Date): void;
    /** **UNSTABLE**: New API, yet to be vetted.
     *
     * Checks if the file resource is a TTY (terminal).
     *
     * ```ts
     * // This example is system and context specific
     * using file = await Deno.open("/dev/tty6");
     * file.isTerminal(); // true
     * ```
     */
    isTerminal(): boolean;
    /** **UNSTABLE**: New API, yet to be vetted.
     *
     * Set TTY to be under raw mode or not. In raw mode, characters are read and
     * returned as is, without being processed. All special processing of
     * characters by the terminal is disabled, including echoing input
     * characters. Reading from a TTY device in raw mode is faster than reading
     * from a TTY device in canonical mode.
     *
     * ```ts
     * using file = await Deno.open("/dev/tty6");
     * file.setRaw(true, { cbreak: true });
     * ```
     */
    setRaw(mode: boolean, options?: SetRawOptions): void;
    /**
     * Acquire an advisory file-system lock for the file.
     *
     * @param [exclusive=false]
     */
    lock(exclusive?: boolean): Promise<void>;
    /**
     * Synchronously acquire an advisory file-system lock synchronously for the file.
     *
     * @param [exclusive=false]
     */
    lockSync(exclusive?: boolean): void;
    /**
     * Release an advisory file-system lock for the file.
     */
    unlock(): Promise<void>;
    /**
     * Synchronously release an advisory file-system lock for the file.
     */
    unlockSync(): void;
    /** Close the file. Closing a file when you are finished with it is
     * important to avoid leaking resources.
     *
     * ```ts
     * using file = await Deno.open("my_file.txt");
     * // do work with "file" object
     * ```
     */
    close(): void;

    [Symbol.dispose](): void;
  }

  /** Gets the size of the console as columns/rows.
   *
   * ```ts
   * const { columns, rows } = Deno.consoleSize();
   * ```
   *
   * This returns the size of the console window as reported by the operating
   * system. It's not a reflection of how many characters will fit within the
   * console window, but can be used as part of that calculation.
   *
   * @category I/O
   */
  export function consoleSize(): {
    columns: number;
    rows: number;
  };

  /** @category I/O */
  export interface SetRawOptions {
    /**
     * The `cbreak` option can be used to indicate that characters that
     * correspond to a signal should still be generated. When disabling raw
     * mode, this option is ignored. This functionality currently only works on
     * Linux and Mac OS.
     */
    cbreak: boolean;
  }

  /** A reference to `stdin` which can be used to read directly from `stdin`.
   *
   * It implements the Deno specific
   * {@linkcode https://jsr.io/@std/io/doc/types/~/Reader | Reader},
   * {@linkcode https://jsr.io/@std/io/doc/types/~/ReaderSync | ReaderSync},
   * and {@linkcode https://jsr.io/@std/io/doc/types/~/Closer | Closer}
   * interfaces as well as provides a {@linkcode ReadableStream} interface.
   *
   * ### Reading chunks from the readable stream
   *
   * ```ts
   * const decoder = new TextDecoder();
   * for await (const chunk of Deno.stdin.readable) {
   *   const text = decoder.decode(chunk);
   *   // do something with the text
   * }
   * ```
   *
   * @category I/O
   */
  export const stdin: {
    /** Read the incoming data from `stdin` into an array buffer (`p`).
     *
     * Resolves to either the number of bytes read during the operation or EOF
     * (`null`) if there was nothing more to read.
     *
     * It is possible for a read to successfully return with `0` bytes. This
     * does not indicate EOF.
     *
     * **It is not guaranteed that the full buffer will be read in a single
     * call.**
     *
     * ```ts
     * // If the text "hello world" is piped into the script:
     * const buf = new Uint8Array(100);
     * const numberOfBytesRead = await Deno.stdin.read(buf); // 11 bytes
     * const text = new TextDecoder().decode(buf);  // "hello world"
     * ```
     *
     * @category I/O
     */
    read(p: Uint8Array): Promise<number | null>;
    /** Synchronously read from the incoming data from `stdin` into an array
     * buffer (`p`).
     *
     * Returns either the number of bytes read during the operation or EOF
     * (`null`) if there was nothing more to read.
     *
     * It is possible for a read to successfully return with `0` bytes. This
     * does not indicate EOF.
     *
     * **It is not guaranteed that the full buffer will be read in a single
     * call.**
     *
     * ```ts
     * // If the text "hello world" is piped into the script:
     * const buf = new Uint8Array(100);
     * const numberOfBytesRead = Deno.stdin.readSync(buf); // 11 bytes
     * const text = new TextDecoder().decode(buf);  // "hello world"
     * ```
     *
     * @category I/O
     */
    readSync(p: Uint8Array): number | null;
    /** Closes `stdin`, freeing the resource.
     *
     * ```ts
     * Deno.stdin.close();
     * ```
     */
    close(): void;
    /** A readable stream interface to `stdin`. */
    readonly readable: ReadableStream<Uint8Array>;
    /**
     * Set TTY to be under raw mode or not. In raw mode, characters are read and
     * returned as is, without being processed. All special processing of
     * characters by the terminal is disabled, including echoing input
     * characters. Reading from a TTY device in raw mode is faster than reading
     * from a TTY device in canonical mode.
     *
     * ```ts
     * Deno.stdin.setRaw(true, { cbreak: true });
     * ```
     *
     * @category I/O
     */
    setRaw(mode: boolean, options?: SetRawOptions): void;
    /**
     * Checks if `stdin` is a TTY (terminal).
     *
     * ```ts
     * // This example is system and context specific
     * Deno.stdin.isTerminal(); // true
     * ```
     *
     * @category I/O
     */
    isTerminal(): boolean;
  };
  /** A reference to `stdout` which can be used to write directly to `stdout`.
   * It implements the Deno specific
   * {@linkcode https://jsr.io/@std/io/doc/types/~/Writer | Writer},
   * {@linkcode https://jsr.io/@std/io/doc/types/~/WriterSync | WriterSync},
   * and {@linkcode https://jsr.io/@std/io/doc/types/~/Closer | Closer} interfaces as well as provides a
   * {@linkcode WritableStream} interface.
   *
   * These are low level constructs, and the {@linkcode console} interface is a
   * more straight forward way to interact with `stdout` and `stderr`.
   *
   * @category I/O
   */
  export const stdout: {
    /** Write the contents of the array buffer (`p`) to `stdout`.
     *
     * Resolves to the number of bytes written.
     *
     * **It is not guaranteed that the full buffer will be written in a single
     * call.**
     *
     * ```ts
     * const encoder = new TextEncoder();
     * const data = encoder.encode("Hello world");
     * const bytesWritten = await Deno.stdout.write(data); // 11
     * ```
     *
     * @category I/O
     */
    write(p: Uint8Array): Promise<number>;
    /** Synchronously write the contents of the array buffer (`p`) to `stdout`.
     *
     * Returns the number of bytes written.
     *
     * **It is not guaranteed that the full buffer will be written in a single
     * call.**
     *
     * ```ts
     * const encoder = new TextEncoder();
     * const data = encoder.encode("Hello world");
     * const bytesWritten = Deno.stdout.writeSync(data); // 11
     * ```
     */
    writeSync(p: Uint8Array): number;
    /** Closes `stdout`, freeing the resource.
     *
     * ```ts
     * Deno.stdout.close();
     * ```
     */
    close(): void;
    /** A writable stream interface to `stdout`. */
    readonly writable: WritableStream<Uint8Array>;
    /**
     * Checks if `stdout` is a TTY (terminal).
     *
     * ```ts
     * // This example is system and context specific
     * Deno.stdout.isTerminal(); // true
     * ```
     *
     * @category I/O
     */
    isTerminal(): boolean;
  };
  /** A reference to `stderr` which can be used to write directly to `stderr`.
   * It implements the Deno specific
   * {@linkcode https://jsr.io/@std/io/doc/types/~/Writer | Writer},
   * {@linkcode https://jsr.io/@std/io/doc/types/~/WriterSync | WriterSync},
   * and {@linkcode https://jsr.io/@std/io/doc/types/~/Closer | Closer} interfaces as well as provides a
   * {@linkcode WritableStream} interface.
   *
   * These are low level constructs, and the {@linkcode console} interface is a
   * more straight forward way to interact with `stdout` and `stderr`.
   *
   * @category I/O
   */
  export const stderr: {
    /** Write the contents of the array buffer (`p`) to `stderr`.
     *
     * Resolves to the number of bytes written.
     *
     * **It is not guaranteed that the full buffer will be written in a single
     * call.**
     *
     * ```ts
     * const encoder = new TextEncoder();
     * const data = encoder.encode("Hello world");
     * const bytesWritten = await Deno.stderr.write(data); // 11
     * ```
     *
     * @category I/O
     */
    write(p: Uint8Array): Promise<number>;
    /** Synchronously write the contents of the array buffer (`p`) to `stderr`.
     *
     * Returns the number of bytes written.
     *
     * **It is not guaranteed that the full buffer will be written in a single
     * call.**
     *
     * ```ts
     * const encoder = new TextEncoder();
     * const data = encoder.encode("Hello world");
     * const bytesWritten = Deno.stderr.writeSync(data); // 11
     * ```
     */
    writeSync(p: Uint8Array): number;
    /** Closes `stderr`, freeing the resource.
     *
     * ```ts
     * Deno.stderr.close();
     * ```
     */
    close(): void;
    /** A writable stream interface to `stderr`. */
    readonly writable: WritableStream<Uint8Array>;
    /**
     * Checks if `stderr` is a TTY (terminal).
     *
     * ```ts
     * // This example is system and context specific
     * Deno.stderr.isTerminal(); // true
     * ```
     *
     * @category I/O
     */
    isTerminal(): boolean;
  };

  /**
   * Options which can be set when doing {@linkcode Deno.open} and
   * {@linkcode Deno.openSync}.
   *
   * @category File System */
  export interface OpenOptions {
    /** Sets the option for read access. This option, when `true`, means that
     * the file should be read-able if opened.
     *
     * @default {true} */
    read?: boolean;
    /** Sets the option for write access. This option, when `true`, means that
     * the file should be write-able if opened. If the file already exists,
     * any write calls on it will overwrite its contents, by default without
     * truncating it.
     *
     * @default {false} */
    write?: boolean;
    /** Sets the option for the append mode. This option, when `true`, means
     * that writes will append to a file instead of overwriting previous
     * contents.
     *
     * Note that setting `{ write: true, append: true }` has the same effect as
     * setting only `{ append: true }`.
     *
     * @default {false} */
    append?: boolean;
    /** Sets the option for truncating a previous file. If a file is
     * successfully opened with this option set it will truncate the file to `0`
     * size if it already exists. The file must be opened with write access
     * for truncate to work.
     *
     * @default {false} */
    truncate?: boolean;
    /** Sets the option to allow creating a new file, if one doesn't already
     * exist at the specified path. Requires write or append access to be
     * used.
     *
     * @default {false} */
    create?: boolean;
    /** If set to `true`, no file, directory, or symlink is allowed to exist at
     * the target location. Requires write or append access to be used. When
     * createNew is set to `true`, create and truncate are ignored.
     *
     * @default {false} */
    createNew?: boolean;
    /** Permissions to use if creating the file (defaults to `0o666`, before
     * the process's umask).
     *
     * Ignored on Windows. */
    mode?: number;
  }

  /**
   * Options which can be set when using {@linkcode Deno.readFile} or
   * {@linkcode Deno.readFileSync}.
   *
   * @category File System */
  export interface ReadFileOptions {
    /**
     * An abort signal to allow cancellation of the file read operation.
     * If the signal becomes aborted the readFile operation will be stopped
     * and the promise returned will be rejected with an AbortError.
     */
    signal?: AbortSignal;
  }

  /**
   * Options which can be set when using {@linkcode Deno.mkdir} and
   * {@linkcode Deno.mkdirSync}.
   *
   * @category File System */
  export interface MkdirOptions {
    /** If set to `true`, means that any intermediate directories will also be
     * created (as with the shell command `mkdir -p`).
     *
     * Intermediate directories are created with the same permissions.
     *
     * When recursive is set to `true`, succeeds silently (without changing any
     * permissions) if a directory already exists at the path, or if the path
     * is a symlink to an existing directory.
     *
     * @default {false} */
    recursive?: boolean;
    /** Permissions to use when creating the directory (defaults to `0o777`,
     * before the process's umask).
     *
     * Ignored on Windows. */
    mode?: number;
  }

  /** Creates a new directory with the specified path.
   *
   * ```ts
   * await Deno.mkdir("new_dir");
   * await Deno.mkdir("nested/directories", { recursive: true });
   * await Deno.mkdir("restricted_access_dir", { mode: 0o700 });
   * ```
   *
   * Defaults to throwing error if the directory already exists.
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function mkdir(
    path: string | URL,
    options?: MkdirOptions,
  ): Promise<void>;

  /** Synchronously creates a new directory with the specified path.
   *
   * ```ts
   * Deno.mkdirSync("new_dir");
   * Deno.mkdirSync("nested/directories", { recursive: true });
   * Deno.mkdirSync("restricted_access_dir", { mode: 0o700 });
   * ```
   *
   * Defaults to throwing error if the directory already exists.
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function mkdirSync(path: string | URL, options?: MkdirOptions): void;

  /**
   * Options which can be set when using {@linkcode Deno.makeTempDir},
   * {@linkcode Deno.makeTempDirSync}, {@linkcode Deno.makeTempFile}, and
   * {@linkcode Deno.makeTempFileSync}.
   *
   * @category File System */
  export interface MakeTempOptions {
    /** Directory where the temporary directory should be created (defaults to
     * the env variable `TMPDIR`, or the system's default, usually `/tmp`).
     *
     * Note that if the passed `dir` is relative, the path returned by
     * `makeTempFile()` and `makeTempDir()` will also be relative. Be mindful of
     * this when changing working directory. */
    dir?: string;
    /** String that should precede the random portion of the temporary
     * directory's name. */
    prefix?: string;
    /** String that should follow the random portion of the temporary
     * directory's name. */
    suffix?: string;
  }

  /** Creates a new temporary directory in the default directory for temporary
   * files, unless `dir` is specified. Other optional options include
   * prefixing and suffixing the directory name with `prefix` and `suffix`
   * respectively.
   *
   * This call resolves to the full path to the newly created directory.
   *
   * Multiple programs calling this function simultaneously will create different
   * directories. It is the caller's responsibility to remove the directory when
   * no longer needed.
   *
   * ```ts
   * const tempDirName0 = await Deno.makeTempDir();  // e.g. /tmp/2894ea76
   * const tempDirName1 = await Deno.makeTempDir({ prefix: 'my_temp' }); // e.g. /tmp/my_temp339c944d
   * ```
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  // TODO(ry) Doesn't check permissions.
  export function makeTempDir(options?: MakeTempOptions): Promise<string>;

  /** Synchronously creates a new temporary directory in the default directory
   * for temporary files, unless `dir` is specified. Other optional options
   * include prefixing and suffixing the directory name with `prefix` and
   * `suffix` respectively.
   *
   * The full path to the newly created directory is returned.
   *
   * Multiple programs calling this function simultaneously will create different
   * directories. It is the caller's responsibility to remove the directory when
   * no longer needed.
   *
   * ```ts
   * const tempDirName0 = Deno.makeTempDirSync();  // e.g. /tmp/2894ea76
   * const tempDirName1 = Deno.makeTempDirSync({ prefix: 'my_temp' });  // e.g. /tmp/my_temp339c944d
   * ```
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  // TODO(ry) Doesn't check permissions.
  export function makeTempDirSync(options?: MakeTempOptions): string;

  /** Creates a new temporary file in the default directory for temporary
   * files, unless `dir` is specified.
   *
   * Other options include prefixing and suffixing the directory name with
   * `prefix` and `suffix` respectively.
   *
   * This call resolves to the full path to the newly created file.
   *
   * Multiple programs calling this function simultaneously will create
   * different files. It is the caller's responsibility to remove the file when
   * no longer needed.
   *
   * ```ts
   * const tmpFileName0 = await Deno.makeTempFile();  // e.g. /tmp/419e0bf2
   * const tmpFileName1 = await Deno.makeTempFile({ prefix: 'my_temp' });  // e.g. /tmp/my_temp754d3098
   * ```
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function makeTempFile(options?: MakeTempOptions): Promise<string>;

  /** Synchronously creates a new temporary file in the default directory for
   * temporary files, unless `dir` is specified.
   *
   * Other options include prefixing and suffixing the directory name with
   * `prefix` and `suffix` respectively.
   *
   * The full path to the newly created file is returned.
   *
   * Multiple programs calling this function simultaneously will create
   * different files. It is the caller's responsibility to remove the file when
   * no longer needed.
   *
   * ```ts
   * const tempFileName0 = Deno.makeTempFileSync(); // e.g. /tmp/419e0bf2
   * const tempFileName1 = Deno.makeTempFileSync({ prefix: 'my_temp' });  // e.g. /tmp/my_temp754d3098
   * ```
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function makeTempFileSync(options?: MakeTempOptions): string;

  /** Changes the permission of a specific file/directory of specified path.
   * Ignores the process's umask.
   *
   * ```ts
   * await Deno.chmod("/path/to/file", 0o666);
   * ```
   *
   * The mode is a sequence of 3 octal numbers. The first/left-most number
   * specifies the permissions for the owner. The second number specifies the
   * permissions for the group. The last/right-most number specifies the
   * permissions for others. For example, with a mode of 0o764, the owner (7)
   * can read/write/execute, the group (6) can read/write and everyone else (4)
   * can read only.
   *
   * | Number | Description |
   * | ------ | ----------- |
   * | 7      | read, write, and execute |
   * | 6      | read and write |
   * | 5      | read and execute |
   * | 4      | read only |
   * | 3      | write and execute |
   * | 2      | write only |
   * | 1      | execute only |
   * | 0      | no permission |
   *
   * NOTE: This API currently throws on Windows
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function chmod(path: string | URL, mode: number): Promise<void>;

  /** Synchronously changes the permission of a specific file/directory of
   * specified path. Ignores the process's umask.
   *
   * ```ts
   * Deno.chmodSync("/path/to/file", 0o666);
   * ```
   *
   * For a full description, see {@linkcode Deno.chmod}.
   *
   * NOTE: This API currently throws on Windows
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function chmodSync(path: string | URL, mode: number): void;

  /** Change owner of a regular file or directory.
   *
   * This functionality is not available on Windows.
   *
   * ```ts
   * await Deno.chown("myFile.txt", 1000, 1002);
   * ```
   *
   * Requires `allow-write` permission.
   *
   * Throws Error (not implemented) if executed on Windows.
   *
   * @tags allow-write
   * @category File System
   *
   * @param path path to the file
   * @param uid user id (UID) of the new owner, or `null` for no change
   * @param gid group id (GID) of the new owner, or `null` for no change
   */
  export function chown(
    path: string | URL,
    uid: number | null,
    gid: number | null,
  ): Promise<void>;

  /** Synchronously change owner of a regular file or directory.
   *
   * This functionality is not available on Windows.
   *
   * ```ts
   * Deno.chownSync("myFile.txt", 1000, 1002);
   * ```
   *
   * Requires `allow-write` permission.
   *
   * Throws Error (not implemented) if executed on Windows.
   *
   * @tags allow-write
   * @category File System
   *
   * @param path path to the file
   * @param uid user id (UID) of the new owner, or `null` for no change
   * @param gid group id (GID) of the new owner, or `null` for no change
   */
  export function chownSync(
    path: string | URL,
    uid: number | null,
    gid: number | null,
  ): void;

  /**
   * Options which can be set when using {@linkcode Deno.remove} and
   * {@linkcode Deno.removeSync}.
   *
   * @category File System */
  export interface RemoveOptions {
    /** If set to `true`, path will be removed even if it's a non-empty directory.
     *
     * @default {false} */
    recursive?: boolean;
  }

  /** Removes the named file or directory.
   *
   * ```ts
   * await Deno.remove("/path/to/empty_dir/or/file");
   * await Deno.remove("/path/to/populated_dir/or/file", { recursive: true });
   * ```
   *
   * Throws error if permission denied, path not found, or path is a non-empty
   * directory and the `recursive` option isn't set to `true`.
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function remove(
    path: string | URL,
    options?: RemoveOptions,
  ): Promise<void>;

  /** Synchronously removes the named file or directory.
   *
   * ```ts
   * Deno.removeSync("/path/to/empty_dir/or/file");
   * Deno.removeSync("/path/to/populated_dir/or/file", { recursive: true });
   * ```
   *
   * Throws error if permission denied, path not found, or path is a non-empty
   * directory and the `recursive` option isn't set to `true`.
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function removeSync(path: string | URL, options?: RemoveOptions): void;

  /** Synchronously renames (moves) `oldpath` to `newpath`. Paths may be files or
   * directories. If `newpath` already exists and is not a directory,
   * `renameSync()` replaces it. OS-specific restrictions may apply when
   * `oldpath` and `newpath` are in different directories.
   *
   * ```ts
   * Deno.renameSync("old/path", "new/path");
   * ```
   *
   * On Unix-like OSes, this operation does not follow symlinks at either path.
   *
   * It varies between platforms when the operation throws errors, and if so what
   * they are. It's always an error to rename anything to a non-empty directory.
   *
   * Requires `allow-read` and `allow-write` permissions.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function renameSync(
    oldpath: string | URL,
    newpath: string | URL,
  ): void;

  /** Renames (moves) `oldpath` to `newpath`. Paths may be files or directories.
   * If `newpath` already exists and is not a directory, `rename()` replaces it.
   * OS-specific restrictions may apply when `oldpath` and `newpath` are in
   * different directories.
   *
   * ```ts
   * await Deno.rename("old/path", "new/path");
   * ```
   *
   * On Unix-like OSes, this operation does not follow symlinks at either path.
   *
   * It varies between platforms when the operation throws errors, and if so
   * what they are. It's always an error to rename anything to a non-empty
   * directory.
   *
   * Requires `allow-read` and `allow-write` permissions.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function rename(
    oldpath: string | URL,
    newpath: string | URL,
  ): Promise<void>;

  /** Asynchronously reads and returns the entire contents of a file as an UTF-8
   *  decoded string. Reading a directory throws an error.
   *
   * ```ts
   * const data = await Deno.readTextFile("hello.txt");
   * console.log(data);
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function readTextFile(
    path: string | URL,
    options?: ReadFileOptions,
  ): Promise<string>;

  /** Synchronously reads and returns the entire contents of a file as an UTF-8
   *  decoded string. Reading a directory throws an error.
   *
   * ```ts
   * const data = Deno.readTextFileSync("hello.txt");
   * console.log(data);
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function readTextFileSync(path: string | URL): string;

  /** Reads and resolves to the entire contents of a file as an array of bytes.
   * `TextDecoder` can be used to transform the bytes to string if required.
   * Reading a directory returns an empty data array.
   *
   * ```ts
   * const decoder = new TextDecoder("utf-8");
   * const data = await Deno.readFile("hello.txt");
   * console.log(decoder.decode(data));
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function readFile(
    path: string | URL,
    options?: ReadFileOptions,
  ): Promise<Uint8Array>;

  /** Synchronously reads and returns the entire contents of a file as an array
   * of bytes. `TextDecoder` can be used to transform the bytes to string if
   * required. Reading a directory returns an empty data array.
   *
   * ```ts
   * const decoder = new TextDecoder("utf-8");
   * const data = Deno.readFileSync("hello.txt");
   * console.log(decoder.decode(data));
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function readFileSync(path: string | URL): Uint8Array;

  /** Provides information about a file and is returned by
   * {@linkcode Deno.stat}, {@linkcode Deno.lstat}, {@linkcode Deno.statSync},
   * and {@linkcode Deno.lstatSync} or from calling `stat()` and `statSync()`
   * on an {@linkcode Deno.FsFile} instance.
   *
   * @category File System
   */
  export interface FileInfo {
    /** True if this is info for a regular file. Mutually exclusive to
     * `FileInfo.isDirectory` and `FileInfo.isSymlink`. */
    isFile: boolean;
    /** True if this is info for a regular directory. Mutually exclusive to
     * `FileInfo.isFile` and `FileInfo.isSymlink`. */
    isDirectory: boolean;
    /** True if this is info for a symlink. Mutually exclusive to
     * `FileInfo.isFile` and `FileInfo.isDirectory`. */
    isSymlink: boolean;
    /** The size of the file, in bytes. */
    size: number;
    /** The last modification time of the file. This corresponds to the `mtime`
     * field from `stat` on Linux/Mac OS and `ftLastWriteTime` on Windows. This
     * may not be available on all platforms. */
    mtime: Date | null;
    /** The last access time of the file. This corresponds to the `atime`
     * field from `stat` on Unix and `ftLastAccessTime` on Windows. This may not
     * be available on all platforms. */
    atime: Date | null;
    /** The creation time of the file. This corresponds to the `birthtime`
     * field from `stat` on Mac/BSD and `ftCreationTime` on Windows. This may
     * not be available on all platforms. */
    birthtime: Date | null;
    /** ID of the device containing the file. */
    dev: number;
    /** Inode number.
     *
     * _Linux/Mac OS only._ */
    ino: number | null;
    /** The underlying raw `st_mode` bits that contain the standard Unix
     * permissions for this file/directory.
     *
     * _Linux/Mac OS only._ */
    mode: number | null;
    /** Number of hard links pointing to this file.
     *
     * _Linux/Mac OS only._ */
    nlink: number | null;
    /** User ID of the owner of this file.
     *
     * _Linux/Mac OS only._ */
    uid: number | null;
    /** Group ID of the owner of this file.
     *
     * _Linux/Mac OS only._ */
    gid: number | null;
    /** Device ID of this file.
     *
     * _Linux/Mac OS only._ */
    rdev: number | null;
    /** Blocksize for filesystem I/O.
     *
     * _Linux/Mac OS only._ */
    blksize: number | null;
    /** Number of blocks allocated to the file, in 512-byte units.
     *
     * _Linux/Mac OS only._ */
    blocks: number | null;
    /**  True if this is info for a block device.
     *
     * _Linux/Mac OS only._ */
    isBlockDevice: boolean | null;
    /**  True if this is info for a char device.
     *
     * _Linux/Mac OS only._ */
    isCharDevice: boolean | null;
    /**  True if this is info for a fifo.
     *
     * _Linux/Mac OS only._ */
    isFifo: boolean | null;
    /**  True if this is info for a socket.
     *
     * _Linux/Mac OS only._ */
    isSocket: boolean | null;
  }

  /** Resolves to the absolute normalized path, with symbolic links resolved.
   *
   * ```ts
   * // e.g. given /home/alice/file.txt and current directory /home/alice
   * await Deno.symlink("file.txt", "symlink_file.txt");
   * const realPath = await Deno.realPath("./file.txt");
   * const realSymLinkPath = await Deno.realPath("./symlink_file.txt");
   * console.log(realPath);  // outputs "/home/alice/file.txt"
   * console.log(realSymLinkPath);  // outputs "/home/alice/file.txt"
   * ```
   *
   * Requires `allow-read` permission for the target path.
   *
   * Also requires `allow-read` permission for the `CWD` if the target path is
   * relative.
   *
   * @tags allow-read
   * @category File System
   */
  export function realPath(path: string | URL): Promise<string>;

  /** Synchronously returns absolute normalized path, with symbolic links
   * resolved.
   *
   * ```ts
   * // e.g. given /home/alice/file.txt and current directory /home/alice
   * Deno.symlinkSync("file.txt", "symlink_file.txt");
   * const realPath = Deno.realPathSync("./file.txt");
   * const realSymLinkPath = Deno.realPathSync("./symlink_file.txt");
   * console.log(realPath);  // outputs "/home/alice/file.txt"
   * console.log(realSymLinkPath);  // outputs "/home/alice/file.txt"
   * ```
   *
   * Requires `allow-read` permission for the target path.
   *
   * Also requires `allow-read` permission for the `CWD` if the target path is
   * relative.
   *
   * @tags allow-read
   * @category File System
   */
  export function realPathSync(path: string | URL): string;

  /**
   * Information about a directory entry returned from {@linkcode Deno.readDir}
   * and {@linkcode Deno.readDirSync}.
   *
   * @category File System */
  export interface DirEntry {
    /** The file name of the entry. It is just the entity name and does not
     * include the full path. */
    name: string;
    /** True if this is info for a regular file. Mutually exclusive to
     * `DirEntry.isDirectory` and `DirEntry.isSymlink`. */
    isFile: boolean;
    /** True if this is info for a regular directory. Mutually exclusive to
     * `DirEntry.isFile` and `DirEntry.isSymlink`. */
    isDirectory: boolean;
    /** True if this is info for a symlink. Mutually exclusive to
     * `DirEntry.isFile` and `DirEntry.isDirectory`. */
    isSymlink: boolean;
  }

  /** Reads the directory given by `path` and returns an async iterable of
   * {@linkcode Deno.DirEntry}. The order of entries is not guaranteed.
   *
   * ```ts
   * for await (const dirEntry of Deno.readDir("/")) {
   *   console.log(dirEntry.name);
   * }
   * ```
   *
   * Throws error if `path` is not a directory.
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function readDir(path: string | URL): AsyncIterable<DirEntry>;

  /** Synchronously reads the directory given by `path` and returns an iterable
   * of {@linkcode Deno.DirEntry}. The order of entries is not guaranteed.
   *
   * ```ts
   * for (const dirEntry of Deno.readDirSync("/")) {
   *   console.log(dirEntry.name);
   * }
   * ```
   *
   * Throws error if `path` is not a directory.
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function readDirSync(path: string | URL): Iterable<DirEntry>;

  /** Copies the contents and permissions of one file to another specified path,
   * by default creating a new file if needed, else overwriting. Fails if target
   * path is a directory or is unwritable.
   *
   * ```ts
   * await Deno.copyFile("from.txt", "to.txt");
   * ```
   *
   * Requires `allow-read` permission on `fromPath`.
   *
   * Requires `allow-write` permission on `toPath`.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function copyFile(
    fromPath: string | URL,
    toPath: string | URL,
  ): Promise<void>;

  /** Synchronously copies the contents and permissions of one file to another
   * specified path, by default creating a new file if needed, else overwriting.
   * Fails if target path is a directory or is unwritable.
   *
   * ```ts
   * Deno.copyFileSync("from.txt", "to.txt");
   * ```
   *
   * Requires `allow-read` permission on `fromPath`.
   *
   * Requires `allow-write` permission on `toPath`.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function copyFileSync(
    fromPath: string | URL,
    toPath: string | URL,
  ): void;

  /** Resolves to the full path destination of the named symbolic link.
   *
   * ```ts
   * await Deno.symlink("./test.txt", "./test_link.txt");
   * const target = await Deno.readLink("./test_link.txt"); // full path of ./test.txt
   * ```
   *
   * Throws TypeError if called with a hard link.
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function readLink(path: string | URL): Promise<string>;

  /** Synchronously returns the full path destination of the named symbolic
   * link.
   *
   * ```ts
   * Deno.symlinkSync("./test.txt", "./test_link.txt");
   * const target = Deno.readLinkSync("./test_link.txt"); // full path of ./test.txt
   * ```
   *
   * Throws TypeError if called with a hard link.
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function readLinkSync(path: string | URL): string;

  /** Resolves to a {@linkcode Deno.FileInfo} for the specified `path`. If
   * `path` is a symlink, information for the symlink will be returned instead
   * of what it points to.
   *
   * ```ts
   * import { assert } from "jsr:@std/assert";
   * const fileInfo = await Deno.lstat("hello.txt");
   * assert(fileInfo.isFile);
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function lstat(path: string | URL): Promise<FileInfo>;

  /** Synchronously returns a {@linkcode Deno.FileInfo} for the specified
   * `path`. If `path` is a symlink, information for the symlink will be
   * returned instead of what it points to.
   *
   * ```ts
   * import { assert } from "jsr:@std/assert";
   * const fileInfo = Deno.lstatSync("hello.txt");
   * assert(fileInfo.isFile);
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function lstatSync(path: string | URL): FileInfo;

  /** Resolves to a {@linkcode Deno.FileInfo} for the specified `path`. Will
   * always follow symlinks.
   *
   * ```ts
   * import { assert } from "jsr:@std/assert";
   * const fileInfo = await Deno.stat("hello.txt");
   * assert(fileInfo.isFile);
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function stat(path: string | URL): Promise<FileInfo>;

  /** Synchronously returns a {@linkcode Deno.FileInfo} for the specified
   * `path`. Will always follow symlinks.
   *
   * ```ts
   * import { assert } from "jsr:@std/assert";
   * const fileInfo = Deno.statSync("hello.txt");
   * assert(fileInfo.isFile);
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function statSync(path: string | URL): FileInfo;

  /** Options for writing to a file.
   *
   * @category File System
   */
  export interface WriteFileOptions {
    /** If set to `true`, will append to a file instead of overwriting previous
     * contents.
     *
     * @default {false} */
    append?: boolean;
    /** Sets the option to allow creating a new file, if one doesn't already
     * exist at the specified path.
     *
     * @default {true} */
    create?: boolean;
    /** If set to `true`, no file, directory, or symlink is allowed to exist at
     * the target location. When createNew is set to `true`, `create` is ignored.
     *
     * @default {false} */
    createNew?: boolean;
    /** Permissions always applied to file. */
    mode?: number;
    /** An abort signal to allow cancellation of the file write operation.
     *
     * If the signal becomes aborted the write file operation will be stopped
     * and the promise returned will be rejected with an {@linkcode AbortError}.
     */
    signal?: AbortSignal;
  }

  /** Write `data` to the given `path`, by default creating a new file if
   * needed, else overwriting.
   *
   * ```ts
   * const encoder = new TextEncoder();
   * const data = encoder.encode("Hello world\n");
   * await Deno.writeFile("hello1.txt", data);  // overwrite "hello1.txt" or create it
   * await Deno.writeFile("hello2.txt", data, { create: false });  // only works if "hello2.txt" exists
   * await Deno.writeFile("hello3.txt", data, { mode: 0o777 });  // set permissions on new file
   * await Deno.writeFile("hello4.txt", data, { append: true });  // add data to the end of the file
   * ```
   *
   * Requires `allow-write` permission, and `allow-read` if `options.create` is
   * `false`.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function writeFile(
    path: string | URL,
    data: Uint8Array | ReadableStream<Uint8Array>,
    options?: WriteFileOptions,
  ): Promise<void>;

  /** Synchronously write `data` to the given `path`, by default creating a new
   * file if needed, else overwriting.
   *
   * ```ts
   * const encoder = new TextEncoder();
   * const data = encoder.encode("Hello world\n");
   * Deno.writeFileSync("hello1.txt", data);  // overwrite "hello1.txt" or create it
   * Deno.writeFileSync("hello2.txt", data, { create: false });  // only works if "hello2.txt" exists
   * Deno.writeFileSync("hello3.txt", data, { mode: 0o777 });  // set permissions on new file
   * Deno.writeFileSync("hello4.txt", data, { append: true });  // add data to the end of the file
   * ```
   *
   * Requires `allow-write` permission, and `allow-read` if `options.create` is
   * `false`.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function writeFileSync(
    path: string | URL,
    data: Uint8Array,
    options?: WriteFileOptions,
  ): void;

  /** Write string `data` to the given `path`, by default creating a new file if
   * needed, else overwriting.
   *
   * ```ts
   * await Deno.writeTextFile("hello1.txt", "Hello world\n");  // overwrite "hello1.txt" or create it
   * ```
   *
   * Requires `allow-write` permission, and `allow-read` if `options.create` is
   * `false`.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function writeTextFile(
    path: string | URL,
    data: string | ReadableStream<string>,
    options?: WriteFileOptions,
  ): Promise<void>;

  /** Synchronously write string `data` to the given `path`, by default creating
   * a new file if needed, else overwriting.
   *
   * ```ts
   * Deno.writeTextFileSync("hello1.txt", "Hello world\n");  // overwrite "hello1.txt" or create it
   * ```
   *
   * Requires `allow-write` permission, and `allow-read` if `options.create` is
   * `false`.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function writeTextFileSync(
    path: string | URL,
    data: string,
    options?: WriteFileOptions,
  ): void;

  /** Truncates (or extends) the specified file, to reach the specified `len`.
   * If `len` is not specified then the entire file contents are truncated.
   *
   * ### Truncate the entire file
   * ```ts
   * await Deno.truncate("my_file.txt");
   * ```
   *
   * ### Truncate part of the file
   *
   * ```ts
   * const file = await Deno.makeTempFile();
   * await Deno.writeTextFile(file, "Hello World");
   * await Deno.truncate(file, 7);
   * const data = await Deno.readFile(file);
   * console.log(new TextDecoder().decode(data));  // "Hello W"
   * ```
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function truncate(name: string, len?: number): Promise<void>;

  /** Synchronously truncates (or extends) the specified file, to reach the
   * specified `len`. If `len` is not specified then the entire file contents
   * are truncated.
   *
   * ### Truncate the entire file
   *
   * ```ts
   * Deno.truncateSync("my_file.txt");
   * ```
   *
   * ### Truncate part of the file
   *
   * ```ts
   * const file = Deno.makeTempFileSync();
   * Deno.writeFileSync(file, new TextEncoder().encode("Hello World"));
   * Deno.truncateSync(file, 7);
   * const data = Deno.readFileSync(file);
   * console.log(new TextDecoder().decode(data));
   * ```
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function truncateSync(name: string, len?: number): void;

  /** @category Runtime
   *
   * @deprecated This will be removed in Deno 2.0.
   */
  export interface OpMetrics {
    opsDispatched: number;
    opsDispatchedSync: number;
    opsDispatchedAsync: number;
    opsDispatchedAsyncUnref: number;
    opsCompleted: number;
    opsCompletedSync: number;
    opsCompletedAsync: number;
    opsCompletedAsyncUnref: number;
    bytesSentControl: number;
    bytesSentData: number;
    bytesReceived: number;
  }

  /**
   * Additional information for FsEvent objects with the "other" kind.
   *
   * - `"rescan"`: rescan notices indicate either a lapse in the events or a
   *    change in the filesystem such that events received so far can no longer
   *    be relied on to represent the state of the filesystem now. An
   *    application that simply reacts to file changes may not care about this.
   *    An application that keeps an in-memory representation of the filesystem
   *    will need to care, and will need to refresh that representation directly
   *    from the filesystem.
   *
   * @category File System
   */
  export type FsEventFlag = "rescan";

  /**
   * Represents a unique file system event yielded by a
   * {@linkcode Deno.FsWatcher}.
   *
   * @category File System */
  export interface FsEvent {
    /** The kind/type of the file system event. */
    kind:
      | "any"
      | "access"
      | "create"
      | "modify"
      | "rename"
      | "remove"
      | "other";
    /** An array of paths that are associated with the file system event. */
    paths: string[];
    /** Any additional flags associated with the event. */
    flag?: FsEventFlag;
  }

  /**
   * Returned by {@linkcode Deno.watchFs}. It is an async iterator yielding up
   * system events. To stop watching the file system by calling `.close()`
   * method.
   *
   * @category File System
   */
  export interface FsWatcher extends AsyncIterable<FsEvent>, Disposable {
    /** Stops watching the file system and closes the watcher resource. */
    close(): void;
    /**
     * Stops watching the file system and closes the watcher resource.
     *
     * @deprecated This will be removed in Deno 2.0. See the
     * {@link https://docs.deno.com/runtime/manual/advanced/migrate_deprecations | Deno 1.x to 2.x Migration Guide}
     * for migration instructions.
     */
    return?(value?: any): Promise<IteratorResult<FsEvent>>;
    [Symbol.asyncIterator](): AsyncIterableIterator<FsEvent>;
  }

  /** Watch for file system events against one or more `paths`, which can be
   * files or directories. These paths must exist already. One user action (e.g.
   * `touch test.file`) can generate multiple file system events. Likewise,
   * one user action can result in multiple file paths in one event (e.g. `mv
   * old_name.txt new_name.txt`).
   *
   * The recursive option is `true` by default and, for directories, will watch
   * the specified directory and all sub directories.
   *
   * Note that the exact ordering of the events can vary between operating
   * systems.
   *
   * ```ts
   * const watcher = Deno.watchFs("/");
   * for await (const event of watcher) {
   *    console.log(">>>> event", event);
   *    // { kind: "create", paths: [ "/foo.txt" ] }
   * }
   * ```
   *
   * Call `watcher.close()` to stop watching.
   *
   * ```ts
   * const watcher = Deno.watchFs("/");
   *
   * setTimeout(() => {
   *   watcher.close();
   * }, 5000);
   *
   * for await (const event of watcher) {
   *    console.log(">>>> event", event);
   * }
   * ```
   *
   * Requires `allow-read` permission.
   *
   * @tags allow-read
   * @category File System
   */
  export function watchFs(
    paths: string | string[],
    options?: { recursive: boolean },
  ): FsWatcher;

  /** Operating signals which can be listened for or sent to sub-processes. What
   * signals and what their standard behaviors are OS dependent.
   *
   * @category Runtime */
  export type Signal =
    | "SIGABRT"
    | "SIGALRM"
    | "SIGBREAK"
    | "SIGBUS"
    | "SIGCHLD"
    | "SIGCONT"
    | "SIGEMT"
    | "SIGFPE"
    | "SIGHUP"
    | "SIGILL"
    | "SIGINFO"
    | "SIGINT"
    | "SIGIO"
    | "SIGPOLL"
    | "SIGUNUSED"
    | "SIGKILL"
    | "SIGPIPE"
    | "SIGPROF"
    | "SIGPWR"
    | "SIGQUIT"
    | "SIGSEGV"
    | "SIGSTKFLT"
    | "SIGSTOP"
    | "SIGSYS"
    | "SIGTERM"
    | "SIGTRAP"
    | "SIGTSTP"
    | "SIGTTIN"
    | "SIGTTOU"
    | "SIGURG"
    | "SIGUSR1"
    | "SIGUSR2"
    | "SIGVTALRM"
    | "SIGWINCH"
    | "SIGXCPU"
    | "SIGXFSZ";

  /** Registers the given function as a listener of the given signal event.
   *
   * ```ts
   * Deno.addSignalListener(
   *   "SIGTERM",
   *   () => {
   *     console.log("SIGTERM!")
   *   }
   * );
   * ```
   *
   * _Note_: On Windows only `"SIGINT"` (CTRL+C) and `"SIGBREAK"` (CTRL+Break)
   * are supported.
   *
   * @category Runtime
   */
  export function addSignalListener(signal: Signal, handler: () => void): void;

  /** Removes the given signal listener that has been registered with
   * {@linkcode Deno.addSignalListener}.
   *
   * ```ts
   * const listener = () => {
   *   console.log("SIGTERM!")
   * };
   * Deno.addSignalListener("SIGTERM", listener);
   * Deno.removeSignalListener("SIGTERM", listener);
   * ```
   *
   * _Note_: On Windows only `"SIGINT"` (CTRL+C) and `"SIGBREAK"` (CTRL+Break)
   * are supported.
   *
   * @category Runtime
   */
  export function removeSignalListener(
    signal: Signal,
    handler: () => void,
  ): void;

  /** Create a child process.
   *
   * If any stdio options are not set to `"piped"`, accessing the corresponding
   * field on the `Command` or its `CommandOutput` will throw a `TypeError`.
   *
   * If `stdin` is set to `"piped"`, the `stdin` {@linkcode WritableStream}
   * needs to be closed manually.
   *
   * `Command` acts as a builder. Each call to {@linkcode Command.spawn} or
   * {@linkcode Command.output} will spawn a new subprocess.
   *
   * @example Spawn a subprocess and pipe the output to a file
   *
   * ```ts
   * const command = new Deno.Command(Deno.execPath(), {
   *   args: [
   *     "eval",
   *     "console.log('Hello World')",
   *   ],
   *   stdin: "piped",
   *   stdout: "piped",
   * });
   * const child = command.spawn();
   *
   * // open a file and pipe the subprocess output to it.
   * child.stdout.pipeTo(
   *   Deno.openSync("output", { write: true, create: true }).writable,
   * );
   *
   * // manually close stdin
   * child.stdin.close();
   * const status = await child.status;
   * ```
   *
   * @example Spawn a subprocess and collect its output
   *
   * ```ts
   * const command = new Deno.Command(Deno.execPath(), {
   *   args: [
   *     "eval",
   *     "console.log('hello'); console.error('world')",
   *   ],
   * });
   * const { code, stdout, stderr } = await command.output();
   * console.assert(code === 0);
   * console.assert("hello\n" === new TextDecoder().decode(stdout));
   * console.assert("world\n" === new TextDecoder().decode(stderr));
   * ```
   *
   * @example Spawn a subprocess and collect its output synchronously
   *
   * ```ts
   * const command = new Deno.Command(Deno.execPath(), {
   *   args: [
   *     "eval",
   *     "console.log('hello'); console.error('world')",
   *   ],
   * });
   * const { code, stdout, stderr } = command.outputSync();
   * console.assert(code === 0);
   * console.assert("hello\n" === new TextDecoder().decode(stdout));
   * console.assert("world\n" === new TextDecoder().decode(stderr));
   * ```
   *
   * @tags allow-run
   * @category Subprocess
   */
  export class Command {
    constructor(command: string | URL, options?: CommandOptions);
    /**
     * Executes the {@linkcode Deno.Command}, waiting for it to finish and
     * collecting all of its output.
     *
     * Will throw an error if `stdin: "piped"` is set.
     *
     * If options `stdout` or `stderr` are not set to `"piped"`, accessing the
     * corresponding field on {@linkcode Deno.CommandOutput} will throw a `TypeError`.
     */
    output(): Promise<CommandOutput>;
    /**
     * Synchronously executes the {@linkcode Deno.Command}, waiting for it to
     * finish and collecting all of its output.
     *
     * Will throw an error if `stdin: "piped"` is set.
     *
     * If options `stdout` or `stderr` are not set to `"piped"`, accessing the
     * corresponding field on {@linkcode Deno.CommandOutput} will throw a `TypeError`.
     */
    outputSync(): CommandOutput;
    /**
     * Spawns a streamable subprocess, allowing to use the other methods.
     */
    spawn(): ChildProcess;
  }

  /**
   * The interface for handling a child process returned from
   * {@linkcode Deno.Command.spawn}.
   *
   * @category Subprocess
   */
  export class ChildProcess implements AsyncDisposable {
    get stdin(): WritableStream<Uint8Array>;
    get stdout(): ReadableStream<Uint8Array>;
    get stderr(): ReadableStream<Uint8Array>;
    readonly pid: number;
    /** Get the status of the child. */
    readonly status: Promise<CommandStatus>;

    /** Waits for the child to exit completely, returning all its output and
     * status. */
    output(): Promise<CommandOutput>;
    /** Kills the process with given {@linkcode Deno.Signal}.
     *
     * Defaults to `SIGTERM` if no signal is provided.
     *
     * @param [signo="SIGTERM"]
     */
    kill(signo?: Signal): void;

    /** Ensure that the status of the child process prevents the Deno process
     * from exiting. */
    ref(): void;
    /** Ensure that the status of the child process does not block the Deno
     * process from exiting. */
    unref(): void;

    [Symbol.asyncDispose](): Promise<void>;
  }

  /**
   * Options which can be set when calling {@linkcode Deno.Command}.
   *
   * @category Subprocess
   */
  export interface CommandOptions {
    /** Arguments to pass to the process. */
    args?: string[];
    /**
     * The working directory of the process.
     *
     * If not specified, the `cwd` of the parent process is used.
     */
    cwd?: string | URL;
    /**
     * Clear environmental variables from parent process.
     *
     * Doesn't guarantee that only `env` variables are present, as the OS may
     * set environmental variables for processes.
     *
     * @default {false}
     */
    clearEnv?: boolean;
    /** Environmental variables to pass to the subprocess. */
    env?: Record<string, string>;
    /**
     * Sets the child process’s user ID. This translates to a setuid call in the
     * child process. Failure in the set uid call will cause the spawn to fail.
     */
    uid?: number;
    /** Similar to `uid`, but sets the group ID of the child process. */
    gid?: number;
    /**
     * An {@linkcode AbortSignal} that allows closing the process using the
     * corresponding {@linkcode AbortController} by sending the process a
     * SIGTERM signal.
     *
     * Not supported in {@linkcode Deno.Command.outputSync}.
     */
    signal?: AbortSignal;

    /** How `stdin` of the spawned process should be handled.
     *
     * Defaults to `"inherit"` for `output` & `outputSync`,
     * and `"inherit"` for `spawn`. */
    stdin?: "piped" | "inherit" | "null";
    /** How `stdout` of the spawned process should be handled.
     *
     * Defaults to `"piped"` for `output` & `outputSync`,
     * and `"inherit"` for `spawn`. */
    stdout?: "piped" | "inherit" | "null";
    /** How `stderr` of the spawned process should be handled.
     *
     * Defaults to `"piped"` for `output` & `outputSync`,
     * and `"inherit"` for `spawn`. */
    stderr?: "piped" | "inherit" | "null";

    /** Skips quoting and escaping of the arguments on windows. This option
     * is ignored on non-windows platforms.
     *
     * @default {false} */
    windowsRawArguments?: boolean;
  }

  /**
   * @category Subprocess
   */
  export interface CommandStatus {
    /** If the child process exits with a 0 status code, `success` will be set
     * to `true`, otherwise `false`. */
    success: boolean;
    /** The exit code of the child process. */
    code: number;
    /** The signal associated with the child process. */
    signal: Signal | null;
  }

  /**
   * The interface returned from calling {@linkcode Deno.Command.output} or
   * {@linkcode Deno.Command.outputSync} which represents the result of spawning the
   * child process.
   *
   * @category Subprocess
   */
  export interface CommandOutput extends CommandStatus {
    /** The buffered output from the child process' `stdout`. */
    readonly stdout: Uint8Array;
    /** The buffered output from the child process' `stderr`. */
    readonly stderr: Uint8Array;
  }

  /** Option which can be specified when performing {@linkcode Deno.inspect}.
   *
   * @category I/O */
  export interface InspectOptions {
    /** Stylize output with ANSI colors.
     *
     * @default {false} */
    colors?: boolean;
    /** Try to fit more than one entry of a collection on the same line.
     *
     * @default {true} */
    compact?: boolean;
    /** Traversal depth for nested objects.
     *
     * @default {4} */
    depth?: number;
    /** The maximum length for an inspection to take up a single line.
     *
     * @default {80} */
    breakLength?: number;
    /** Whether or not to escape sequences.
     *
     * @default {true} */
    escapeSequences?: boolean;
    /** The maximum number of iterable entries to print.
     *
     * @default {100} */
    iterableLimit?: number;
    /** Show a Proxy's target and handler.
     *
     * @default {false} */
    showProxy?: boolean;
    /** Sort Object, Set and Map entries by key.
     *
     * @default {false} */
    sorted?: boolean;
    /** Add a trailing comma for multiline collections.
     *
     * @default {false} */
    trailingComma?: boolean;
    /** Evaluate the result of calling getters.
     *
     * @default {false} */
    getters?: boolean;
    /** Show an object's non-enumerable properties.
     *
     * @default {false} */
    showHidden?: boolean;
    /** The maximum length of a string before it is truncated with an
     * ellipsis. */
    strAbbreviateSize?: number;
  }

  /** Converts the input into a string that has the same format as printed by
   * `console.log()`.
   *
   * ```ts
   * const obj = {
   *   a: 10,
   *   b: "hello",
   * };
   * const objAsString = Deno.inspect(obj); // { a: 10, b: "hello" }
   * console.log(obj);  // prints same value as objAsString, e.g. { a: 10, b: "hello" }
   * ```
   *
   * A custom inspect functions can be registered on objects, via the symbol
   * `Symbol.for("Deno.customInspect")`, to control and customize the output
   * of `inspect()` or when using `console` logging:
   *
   * ```ts
   * class A {
   *   x = 10;
   *   y = "hello";
   *   [Symbol.for("Deno.customInspect")]() {
   *     return `x=${this.x}, y=${this.y}`;
   *   }
   * }
   *
   * const inStringFormat = Deno.inspect(new A()); // "x=10, y=hello"
   * console.log(inStringFormat);  // prints "x=10, y=hello"
   * ```
   *
   * A depth can be specified by using the `depth` option:
   *
   * ```ts
   * Deno.inspect({a: {b: {c: {d: 'hello'}}}}, {depth: 2}); // { a: { b: [Object] } }
   * ```
   *
   * @category I/O
   */
  export function inspect(value: unknown, options?: InspectOptions): string;

  /** The name of a privileged feature which needs permission.
   *
   * @category Permissions
   */
  export type PermissionName =
    | "run"
    | "read"
    | "write"
    | "net"
    | "env"
    | "sys"
    | "ffi";

  /** The current status of the permission:
   *
   * - `"granted"` - the permission has been granted.
   * - `"denied"` - the permission has been explicitly denied.
   * - `"prompt"` - the permission has not explicitly granted nor denied.
   *
   * @category Permissions
   */
  export type PermissionState =
    | "granted"
    | "denied"
    | "prompt";

  /** The permission descriptor for the `allow-run` and `deny-run` permissions, which controls
   * access to what sub-processes can be executed by Deno. The option `command`
   * allows scoping the permission to a specific executable.
   *
   * **Warning, in practice, `allow-run` is effectively the same as `allow-all`
   * in the sense that malicious code could execute any arbitrary code on the
   * host.**
   *
   * @category Permissions */
  export interface RunPermissionDescriptor {
    name: "run";
    /** An `allow-run` or `deny-run` permission can be scoped to a specific executable,
     * which would be relative to the start-up CWD of the Deno CLI. */
    command?: string | URL;
  }

  /** The permission descriptor for the `allow-read` and `deny-read` permissions, which controls
   * access to reading resources from the local host. The option `path` allows
   * scoping the permission to a specific path (and if the path is a directory
   * any sub paths).
   *
   * Permission granted under `allow-read` only allows runtime code to attempt
   * to read, the underlying operating system may apply additional permissions.
   *
   * @category Permissions */
  export interface ReadPermissionDescriptor {
    name: "read";
    /** An `allow-read` or `deny-read` permission can be scoped to a specific path (and if
     * the path is a directory, any sub paths). */
    path?: string | URL;
  }

  /** The permission descriptor for the `allow-write` and `deny-write` permissions, which
   * controls access to writing to resources from the local host. The option
   * `path` allow scoping the permission to a specific path (and if the path is
   * a directory any sub paths).
   *
   * Permission granted under `allow-write` only allows runtime code to attempt
   * to write, the underlying operating system may apply additional permissions.
   *
   * @category Permissions */
  export interface WritePermissionDescriptor {
    name: "write";
    /** An `allow-write` or `deny-write` permission can be scoped to a specific path (and if
     * the path is a directory, any sub paths). */
    path?: string | URL;
  }

  /** The permission descriptor for the `allow-net` and `deny-net` permissions, which controls
   * access to opening network ports and connecting to remote hosts via the
   * network. The option `host` allows scoping the permission for outbound
   * connection to a specific host and port.
   *
   * @category Permissions */
  export interface NetPermissionDescriptor {
    name: "net";
    /** Optional host string of the form `"<hostname>[:<port>]"`. Examples:
     *
     *      "github.com"
     *      "deno.land:8080"
     */
    host?: string;
  }

  /** The permission descriptor for the `allow-env` and `deny-env` permissions, which controls
   * access to being able to read and write to the process environment variables
   * as well as access other information about the environment. The option
   * `variable` allows scoping the permission to a specific environment
   * variable.
   *
   * @category Permissions */
  export interface EnvPermissionDescriptor {
    name: "env";
    /** Optional environment variable name (e.g. `PATH`). */
    variable?: string;
  }

  /** The permission descriptor for the `allow-sys` and `deny-sys` permissions, which controls
   * access to sensitive host system information, which malicious code might
   * attempt to exploit. The option `kind` allows scoping the permission to a
   * specific piece of information.
   *
   * @category Permissions */
  export interface SysPermissionDescriptor {
    name: "sys";
    /** The specific information to scope the permission to. */
    kind?:
      | "loadavg"
      | "hostname"
      | "systemMemoryInfo"
      | "networkInterfaces"
      | "osRelease"
      | "osUptime"
      | "uid"
      | "gid"
      | "username"
      | "cpus"
      | "homedir"
      | "statfs"
      | "getPriority"
      | "setPriority";
  }

  /** The permission descriptor for the `allow-ffi` and `deny-ffi` permissions, which controls
   * access to loading _foreign_ code and interfacing with it via the
   * [Foreign Function Interface API](https://docs.deno.com/runtime/manual/runtime/ffi_api)
   * available in Deno.  The option `path` allows scoping the permission to a
   * specific path on the host.
   *
   * @category Permissions */
  export interface FfiPermissionDescriptor {
    name: "ffi";
    /** Optional path on the local host to scope the permission to. */
    path?: string | URL;
  }

  /** Permission descriptors which define a permission and can be queried,
   * requested, or revoked.
   *
   * View the specifics of the individual descriptors for more information about
   * each permission kind.
   *
   * @category Permissions
   */
  export type PermissionDescriptor =
    | RunPermissionDescriptor
    | ReadPermissionDescriptor
    | WritePermissionDescriptor
    | NetPermissionDescriptor
    | EnvPermissionDescriptor
    | SysPermissionDescriptor
    | FfiPermissionDescriptor;

  /** The interface which defines what event types are supported by
   * {@linkcode PermissionStatus} instances.
   *
   * @category Permissions */
  export interface PermissionStatusEventMap {
    "change": Event;
  }

  /** An {@linkcode EventTarget} returned from the {@linkcode Deno.permissions}
   * API which can provide updates to any state changes of the permission.
   *
   * @category Permissions */
  export class PermissionStatus extends EventTarget {
    // deno-lint-ignore no-explicit-any
    onchange: ((this: PermissionStatus, ev: Event) => any) | null;
    readonly state: PermissionState;
    /**
     * Describes if permission is only granted partially, eg. an access
     * might be granted to "/foo" directory, but denied for "/foo/bar".
     * In such case this field will be set to `true` when querying for
     * read permissions of "/foo" directory.
     */
    readonly partial: boolean;
    addEventListener<K extends keyof PermissionStatusEventMap>(
      type: K,
      listener: (
        this: PermissionStatus,
        ev: PermissionStatusEventMap[K],
      ) => any,
      options?: boolean | AddEventListenerOptions,
    ): void;
    addEventListener(
      type: string,
      listener: EventListenerOrEventListenerObject,
      options?: boolean | AddEventListenerOptions,
    ): void;
    removeEventListener<K extends keyof PermissionStatusEventMap>(
      type: K,
      listener: (
        this: PermissionStatus,
        ev: PermissionStatusEventMap[K],
      ) => any,
      options?: boolean | EventListenerOptions,
    ): void;
    removeEventListener(
      type: string,
      listener: EventListenerOrEventListenerObject,
      options?: boolean | EventListenerOptions,
    ): void;
  }

  /**
   * Deno's permission management API.
   *
   * The class which provides the interface for the {@linkcode Deno.permissions}
   * global instance and is based on the web platform
   * [Permissions API](https://developer.mozilla.org/en-US/docs/Web/API/Permissions_API),
   * though some proposed parts of the API which are useful in a server side
   * runtime context were removed or abandoned in the web platform specification
   * which is why it was chosen to locate it in the {@linkcode Deno} namespace
   * instead.
   *
   * By default, if the `stdin`/`stdout` is TTY for the Deno CLI (meaning it can
   * send and receive text), then the CLI will prompt the user to grant
   * permission when an un-granted permission is requested. This behavior can
   * be changed by using the `--no-prompt` command at startup. When prompting
   * the CLI will request the narrowest permission possible, potentially making
   * it annoying to the user. The permissions APIs allow the code author to
   * request a wider set of permissions at one time in order to provide a better
   * user experience.
   *
   * @category Permissions */
  export class Permissions {
    /** Resolves to the current status of a permission.
     *
     * Note, if the permission is already granted, `request()` will not prompt
     * the user again, therefore `query()` is only necessary if you are going
     * to react differently existing permissions without wanting to modify them
     * or prompt the user to modify them.
     *
     * ```ts
     * const status = await Deno.permissions.query({ name: "read", path: "/etc" });
     * console.log(status.state);
     * ```
     */
    query(desc: PermissionDescriptor): Promise<PermissionStatus>;

    /** Returns the current status of a permission.
     *
     * Note, if the permission is already granted, `request()` will not prompt
     * the user again, therefore `querySync()` is only necessary if you are going
     * to react differently existing permissions without wanting to modify them
     * or prompt the user to modify them.
     *
     * ```ts
     * const status = Deno.permissions.querySync({ name: "read", path: "/etc" });
     * console.log(status.state);
     * ```
     */
    querySync(desc: PermissionDescriptor): PermissionStatus;

    /** Revokes a permission, and resolves to the state of the permission.
     *
     * ```ts
     * import { assert } from "jsr:@std/assert";
     *
     * const status = await Deno.permissions.revoke({ name: "run" });
     * assert(status.state !== "granted")
     * ```
     */
    revoke(desc: PermissionDescriptor): Promise<PermissionStatus>;

    /** Revokes a permission, and returns the state of the permission.
     *
     * ```ts
     * import { assert } from "jsr:@std/assert";
     *
     * const status = Deno.permissions.revokeSync({ name: "run" });
     * assert(status.state !== "granted")
     * ```
     */
    revokeSync(desc: PermissionDescriptor): PermissionStatus;

    /** Requests the permission, and resolves to the state of the permission.
     *
     * If the permission is already granted, the user will not be prompted to
     * grant the permission again.
     *
     * ```ts
     * const status = await Deno.permissions.request({ name: "env" });
     * if (status.state === "granted") {
     *   console.log("'env' permission is granted.");
     * } else {
     *   console.log("'env' permission is denied.");
     * }
     * ```
     */
    request(desc: PermissionDescriptor): Promise<PermissionStatus>;

    /** Requests the permission, and returns the state of the permission.
     *
     * If the permission is already granted, the user will not be prompted to
     * grant the permission again.
     *
     * ```ts
     * const status = Deno.permissions.requestSync({ name: "env" });
     * if (status.state === "granted") {
     *   console.log("'env' permission is granted.");
     * } else {
     *   console.log("'env' permission is denied.");
     * }
     * ```
     */
    requestSync(desc: PermissionDescriptor): PermissionStatus;
  }

  /** Deno's permission management API.
   *
   * It is a singleton instance of the {@linkcode Permissions} object and is
   * based on the web platform
   * [Permissions API](https://developer.mozilla.org/en-US/docs/Web/API/Permissions_API),
   * though some proposed parts of the API which are useful in a server side
   * runtime context were removed or abandoned in the web platform specification
   * which is why it was chosen to locate it in the {@linkcode Deno} namespace
   * instead.
   *
   * By default, if the `stdin`/`stdout` is TTY for the Deno CLI (meaning it can
   * send and receive text), then the CLI will prompt the user to grant
   * permission when an un-granted permission is requested. This behavior can
   * be changed by using the `--no-prompt` command at startup. When prompting
   * the CLI will request the narrowest permission possible, potentially making
   * it annoying to the user. The permissions APIs allow the code author to
   * request a wider set of permissions at one time in order to provide a better
   * user experience.
   *
   * Requesting already granted permissions will not prompt the user and will
   * return that the permission was granted.
   *
   * ### Querying
   *
   * ```ts
   * const status = await Deno.permissions.query({ name: "read", path: "/etc" });
   * console.log(status.state);
   * ```
   *
   * ```ts
   * const status = Deno.permissions.querySync({ name: "read", path: "/etc" });
   * console.log(status.state);
   * ```
   *
   * ### Revoking
   *
   * ```ts
   * import { assert } from "jsr:@std/assert";
   *
   * const status = await Deno.permissions.revoke({ name: "run" });
   * assert(status.state !== "granted")
   * ```
   *
   * ```ts
   * import { assert } from "jsr:@std/assert";
   *
   * const status = Deno.permissions.revokeSync({ name: "run" });
   * assert(status.state !== "granted")
   * ```
   *
   * ### Requesting
   *
   * ```ts
   * const status = await Deno.permissions.request({ name: "env" });
   * if (status.state === "granted") {
   *   console.log("'env' permission is granted.");
   * } else {
   *   console.log("'env' permission is denied.");
   * }
   * ```
   *
   * ```ts
   * const status = Deno.permissions.requestSync({ name: "env" });
   * if (status.state === "granted") {
   *   console.log("'env' permission is granted.");
   * } else {
   *   console.log("'env' permission is denied.");
   * }
   * ```
   *
   * @category Permissions
   */
  export const permissions: Permissions;

  /** Information related to the build of the current Deno runtime.
   *
   * Users are discouraged from code branching based on this information, as
   * assumptions about what is available in what build environment might change
   * over time. Developers should specifically sniff out the features they
   * intend to use.
   *
   * The intended use for the information is for logging and debugging purposes.
   *
   * @category Runtime
   */
  export const build: {
    /** The [LLVM](https://llvm.org/) target triple, which is the combination
     * of `${arch}-${vendor}-${os}` and represent the specific build target that
     * the current runtime was built for. */
    target: string;
    /** Instruction set architecture that the Deno CLI was built for. */
    arch: "x86_64" | "aarch64";
    /** The operating system that the Deno CLI was built for. `"darwin"` is
     * also known as OSX or MacOS. */
    os:
      | "darwin"
      | "linux"
      | "android"
      | "windows"
      | "freebsd"
      | "netbsd"
      | "aix"
      | "solaris"
      | "illumos";
    /** The computer vendor that the Deno CLI was built for. */
    vendor: string;
    /** Optional environment flags that were set for this build of Deno CLI. */
    env?: string;
  };

  /** Version information related to the current Deno CLI runtime environment.
   *
   * Users are discouraged from code branching based on this information, as
   * assumptions about what is available in what build environment might change
   * over time. Developers should specifically sniff out the features they
   * intend to use.
   *
   * The intended use for the information is for logging and debugging purposes.
   *
   * @category Runtime
   */
  export const version: {
    /** Deno CLI's version. For example: `"1.26.0"`. */
    deno: string;
    /** The V8 version used by Deno. For example: `"10.7.100.0"`.
     *
     * V8 is the underlying JavaScript runtime platform that Deno is built on
     * top of. */
    v8: string;
    /** The TypeScript version used by Deno. For example: `"4.8.3"`.
     *
     * A version of the TypeScript type checker and language server is built-in
     * to the Deno CLI. */
    typescript: string;
  };

  /** Returns the script arguments to the program.
   *
   * Give the following command line invocation of Deno:
   *
   * ```sh
   * deno run --allow-read https://examples.deno.land/command-line-arguments.ts Sushi
   * ```
   *
   * Then `Deno.args` will contain:
   *
   * ```ts
   * [ "Sushi" ]
   * ```
   *
   * If you are looking for a structured way to parse arguments, there is
   * [`parseArgs()`](https://jsr.io/@std/cli/doc/parse-args/~/parseArgs) from
   * the Deno Standard Library.
   *
   * @category Runtime
   */
  export const args: string[];

  /** The URL of the entrypoint module entered from the command-line. It
   * requires read permission to the CWD.
   *
   * Also see {@linkcode ImportMeta} for other related information.
   *
   * @tags allow-read
   * @category Runtime
   */
  export const mainModule: string;

  /** Options that can be used with {@linkcode symlink} and
   * {@linkcode symlinkSync}.
   *
   * @category File System */
  export interface SymlinkOptions {
    /** Specify the symbolic link type as file, directory or NTFS junction. This
     * option only applies to Windows and is ignored on other operating systems. */
    type: "file" | "dir" | "junction";
  }

  /**
   * Creates `newpath` as a symbolic link to `oldpath`.
   *
   * The `options.type` parameter can be set to `"file"`, `"dir"` or `"junction"`.
   * This argument is only available on Windows and ignored on other platforms.
   *
   * ```ts
   * await Deno.symlink("old/name", "new/name");
   * ```
   *
   * Requires full `allow-read` and `allow-write` permissions.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function symlink(
    oldpath: string | URL,
    newpath: string | URL,
    options?: SymlinkOptions,
  ): Promise<void>;

  /**
   * Creates `newpath` as a symbolic link to `oldpath`.
   *
   * The `options.type` parameter can be set to `"file"`, `"dir"` or `"junction"`.
   * This argument is only available on Windows and ignored on other platforms.
   *
   * ```ts
   * Deno.symlinkSync("old/name", "new/name");
   * ```
   *
   * Requires full `allow-read` and `allow-write` permissions.
   *
   * @tags allow-read, allow-write
   * @category File System
   */
  export function symlinkSync(
    oldpath: string | URL,
    newpath: string | URL,
    options?: SymlinkOptions,
  ): void;

  /**
   * Synchronously changes the access (`atime`) and modification (`mtime`) times
   * of a file system object referenced by `path`. Given times are either in
   * seconds (UNIX epoch time) or as `Date` objects.
   *
   * ```ts
   * Deno.utimeSync("myfile.txt", 1556495550, new Date());
   * ```
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function utimeSync(
    path: string | URL,
    atime: number | Date,
    mtime: number | Date,
  ): void;

  /**
   * Changes the access (`atime`) and modification (`mtime`) times of a file
   * system object referenced by `path`. Given times are either in seconds
   * (UNIX epoch time) or as `Date` objects.
   *
   * ```ts
   * await Deno.utime("myfile.txt", 1556495550, new Date());
   * ```
   *
   * Requires `allow-write` permission.
   *
   * @tags allow-write
   * @category File System
   */
  export function utime(
    path: string | URL,
    atime: number | Date,
    mtime: number | Date,
  ): Promise<void>;

  /** Retrieve the process umask.  If `mask` is provided, sets the process umask.
   * This call always returns what the umask was before the call.
   *
   * ```ts
   * console.log(Deno.umask());  // e.g. 18 (0o022)
   * const prevUmaskValue = Deno.umask(0o077);  // e.g. 18 (0o022)
   * console.log(Deno.umask());  // e.g. 63 (0o077)
   * ```
   *
   * This API is under consideration to determine if permissions are required to
   * call it.
   *
   * *Note*: This API is not implemented on Windows
   *
   * @category File System
   */
  export function umask(mask?: number): number;

  /** The object that is returned from a {@linkcode Deno.upgradeWebSocket}
   * request.
   *
   * @category Web Sockets */
  export interface WebSocketUpgrade {
    /** The response object that represents the HTTP response to the client,
     * which should be used to the {@linkcode RequestEvent} `.respondWith()` for
     * the upgrade to be successful. */
    response: Response;
    /** The {@linkcode WebSocket} interface to communicate to the client via a
     * web socket. */
    socket: WebSocket;
  }

  /** Options which can be set when performing a
   * {@linkcode Deno.upgradeWebSocket} upgrade of a {@linkcode Request}
   *
   * @category Web Sockets */
  export interface UpgradeWebSocketOptions {
    /** Sets the `.protocol` property on the client side web socket to the
     * value provided here, which should be one of the strings specified in the
     * `protocols` parameter when requesting the web socket. This is intended
     * for clients and servers to specify sub-protocols to use to communicate to
     * each other. */
    protocol?: string;
    /** If the client does not respond to this frame with a
     * `pong` within the timeout specified, the connection is deemed
     * unhealthy and is closed. The `close` and `error` event will be emitted.
     *
     * The unit is seconds, with a default of 30.
     * Set to `0` to disable timeouts. */
    idleTimeout?: number;
  }

  /**
   * Upgrade an incoming HTTP request to a WebSocket.
   *
   * Given a {@linkcode Request}, returns a pair of {@linkcode WebSocket} and
   * {@linkcode Response} instances. The original request must be responded to
   * with the returned response for the websocket upgrade to be successful.
   *
   * ```ts
   * Deno.serve((req) => {
   *   if (req.headers.get("upgrade") !== "websocket") {
   *     return new Response(null, { status: 501 });
   *   }
   *   const { socket, response } = Deno.upgradeWebSocket(req);
   *   socket.addEventListener("open", () => {
   *     console.log("a client connected!");
   *   });
   *   socket.addEventListener("message", (event) => {
   *     if (event.data === "ping") {
   *       socket.send("pong");
   *     }
   *   });
   *   return response;
   * });
   * ```
   *
   * If the request body is disturbed (read from) before the upgrade is
   * completed, upgrading fails.
   *
   * This operation does not yet consume the request or open the websocket. This
   * only happens once the returned response has been passed to `respondWith()`.
   *
   * @category Web Sockets
   */
  export function upgradeWebSocket(
    request: Request,
    options?: UpgradeWebSocketOptions,
  ): WebSocketUpgrade;

  /** Send a signal to process under given `pid`. The value and meaning of the
   * `signal` to the process is operating system and process dependant.
   * {@linkcode Signal} provides the most common signals. Default signal
   * is `"SIGTERM"`.
   *
   * The term `kill` is adopted from the UNIX-like command line command `kill`
   * which also signals processes.
   *
   * If `pid` is negative, the signal will be sent to the process group
   * identified by `pid`. An error will be thrown if a negative `pid` is used on
   * Windows.
   *
   * ```ts
   * const command = new Deno.Command("sleep", { args: ["10000"] });
   * const child = command.spawn();
   *
   * Deno.kill(child.pid, "SIGINT");
   * ```
   *
   * Requires `allow-run` permission.
   *
   * @tags allow-run
   * @category Subprocess
   */
  export function kill(pid: number, signo?: Signal): void;

  /** The type of the resource record to resolve via DNS using
   * {@linkcode Deno.resolveDns}.
   *
   * Only the listed types are supported currently.
   *
   * @category Network
   */
  export type RecordType =
    | "A"
    | "AAAA"
    | "ANAME"
    | "CAA"
    | "CNAME"
    | "MX"
    | "NAPTR"
    | "NS"
    | "PTR"
    | "SOA"
    | "SRV"
    | "TXT";

  /**
   * Options which can be set when using {@linkcode Deno.resolveDns}.
   *
   * @category Network */
  export interface ResolveDnsOptions {
    /** The name server to be used for lookups.
     *
     * If not specified, defaults to the system configuration. For example
     * `/etc/resolv.conf` on Unix-like systems. */
    nameServer?: {
      /** The IP address of the name server. */
      ipAddr: string;
      /** The port number the query will be sent to.
       *
       * @default {53} */
      port?: number;
    };
    /**
     * An abort signal to allow cancellation of the DNS resolution operation.
     * If the signal becomes aborted the resolveDns operation will be stopped
     * and the promise returned will be rejected with an AbortError.
     */
    signal?: AbortSignal;
  }

  /** If {@linkcode Deno.resolveDns} is called with `"CAA"` record type
   * specified, it will resolve with an array of objects with this interface.
   *
   * @category Network
   */
  export interface CaaRecord {
    /** If `true`, indicates that the corresponding property tag **must** be
     * understood if the semantics of the CAA record are to be correctly
     * interpreted by an issuer.
     *
     * Issuers **must not** issue certificates for a domain if the relevant CAA
     * Resource Record set contains unknown property tags that have `critical`
     * set. */
    critical: boolean;
    /** An string that represents the identifier of the property represented by
     * the record. */
    tag: string;
    /** The value associated with the tag. */
    value: string;
  }

  /** If {@linkcode Deno.resolveDns} is called with `"MX"` record type
   * specified, it will return an array of objects with this interface.
   *
   * @category Network */
  export interface MxRecord {
    /** A priority value, which is a relative value compared to the other
     * preferences of MX records for the domain. */
    preference: number;
    /** The server that mail should be delivered to. */
    exchange: string;
  }

  /** If {@linkcode Deno.resolveDns} is called with `"NAPTR"` record type
   * specified, it will return an array of objects with this interface.
   *
   * @category Network */
  export interface NaptrRecord {
    order: number;
    preference: number;
    flags: string;
    services: string;
    regexp: string;
    replacement: string;
  }

  /** If {@linkcode Deno.resolveDns} is called with `"SOA"` record type
   * specified, it will return an array of objects with this interface.
   *
   * @category Network */
  export interface SoaRecord {
    mname: string;
    rname: string;
    serial: number;
    refresh: number;
    retry: number;
    expire: number;
    minimum: number;
  }

  /** If {@linkcode Deno.resolveDns} is called with `"SRV"` record type
   * specified, it will return an array of objects with this interface.
   *
   * @category Network
   */
  export interface SrvRecord {
    priority: number;
    weight: number;
    port: number;
    target: string;
  }

  /**
   * Performs DNS resolution against the given query, returning resolved
   * records.
   *
   * Fails in the cases such as:
   *
   * - the query is in invalid format.
   * - the options have an invalid parameter. For example `nameServer.port` is
   *   beyond the range of 16-bit unsigned integer.
   * - the request timed out.
   *
   * ```ts
   * const a = await Deno.resolveDns("example.com", "A");
   *
   * const aaaa = await Deno.resolveDns("example.com", "AAAA", {
   *   nameServer: { ipAddr: "8.8.8.8", port: 53 },
   * });
   * ```
   *
   * Requires `allow-net` permission.
   *
   * @tags allow-net
   * @category Network
   */
  export function resolveDns(
    query: string,
    recordType: "A" | "AAAA" | "ANAME" | "CNAME" | "NS" | "PTR",
    options?: ResolveDnsOptions,
  ): Promise<string[]>;

  /**
   * Performs DNS resolution against the given query, returning resolved
   * records.
   *
   * Fails in the cases such as:
   *
   * - the query is in invalid format.
   * - the options have an invalid parameter. For example `nameServer.port` is
   *   beyond the range of 16-bit unsigned integer.
   * - the request timed out.
   *
   * ```ts
   * const a = await Deno.resolveDns("example.com", "A");
   *
   * const aaaa = await Deno.resolveDns("example.com", "AAAA", {
   *   nameServer: { ipAddr: "8.8.8.8", port: 53 },
   * });
   * ```
   *
   * Requires `allow-net` permission.
   *
   * @tags allow-net
   * @category Network
   */
  export function resolveDns(
    query: string,
    recordType: "CAA",
    options?: ResolveDnsOptions,
  ): Promise<CaaRecord[]>;

  /**
   * Performs DNS resolution against the given query, returning resolved
   * records.
   *
   * Fails in the cases such as:
   *
   * - the query is in invalid format.
   * - the options have an invalid parameter. For example `nameServer.port` is
   *   beyond the range of 16-bit unsigned integer.
   * - the request timed out.
   *
   * ```ts
   * const a = await Deno.resolveDns("example.com", "A");
   *
   * const aaaa = await Deno.resolveDns("example.com", "AAAA", {
   *   nameServer: { ipAddr: "8.8.8.8", port: 53 },
   * });
   * ```
   *
   * Requires `allow-net` permission.
   *
   * @tags allow-net
   * @category Network
   */
  export function resolveDns(
    query: string,
    recordType: "MX",
    options?: ResolveDnsOptions,
  ): Promise<MxRecord[]>;

  /**
   * Performs DNS resolution against the given query, returning resolved
   * records.
   *
   * Fails in the cases such as:
   *
   * - the query is in invalid format.
   * - the options have an invalid parameter. For example `nameServer.port` is
   *   beyond the range of 16-bit unsigned integer.
   * - the request timed out.
   *
   * ```ts
   * const a = await Deno.resolveDns("example.com", "A");
   *
   * const aaaa = await Deno.resolveDns("example.com", "AAAA", {
   *   nameServer: { ipAddr: "8.8.8.8", port: 53 },
   * });
   * ```
   *
   * Requires `allow-net` permission.
   *
   * @tags allow-net
   * @category Network
   */
  export function resolveDns(
    query: string,
    recordType: "NAPTR",
    options?: ResolveDnsOptions,
  ): Promise<NaptrRecord[]>;

  /**
   * Performs DNS resolution against the given query, returning resolved
   * records.
   *
   * Fails in the cases such as:
   *
   * - the query is in invalid format.
   * - the options have an invalid parameter. For example `nameServer.port` is
   *   beyond the range of 16-bit unsigned integer.
   * - the request timed out.
   *
   * ```ts
   * const a = await Deno.resolveDns("example.com", "A");
   *
   * const aaaa = await Deno.resolveDns("example.com", "AAAA", {
   *   nameServer: { ipAddr: "8.8.8.8", port: 53 },
   * });
   * ```
   *
   * Requires `allow-net` permission.
   *
   * @tags allow-net
   * @category Network
   */
  export function resolveDns(
    query: string,
    recordType: "SOA",
    options?: ResolveDnsOptions,
  ): Promise<SoaRecord[]>;

  /**
   * Performs DNS resolution against the given query, returning resolved
   * records.
   *
   * Fails in the cases such as:
   *
   * - the query is in invalid format.
   * - the options have an invalid parameter. For example `nameServer.port` is
   *   beyond the range of 16-bit unsigned integer.
   * - the request timed out.
   *
   * ```ts
   * const a = await Deno.resolveDns("example.com", "A");
   *
   * const aaaa = await Deno.resolveDns("example.com", "AAAA", {
   *   nameServer: { ipAddr: "8.8.8.8", port: 53 },
   * });
   * ```
   *
   * Requires `allow-net` permission.
   *
   * @tags allow-net
   * @category Network
   */
  export function resolveDns(
    query: string,
    recordType: "SRV",
    options?: ResolveDnsOptions,
  ): Promise<SrvRecord[]>;

  /**
   * Performs DNS resolution against the given query, returning resolved
   * records.
   *
   * Fails in the cases such as:
   *
   * - the query is in invalid format.
   * - the options have an invalid parameter. For example `nameServer.port` is
   *   beyond the range of 16-bit unsigned integer.
   * - the request timed out.
   *
   * ```ts
   * const a = await Deno.resolveDns("example.com", "A");
   *
   * const aaaa = await Deno.resolveDns("example.com", "AAAA", {
   *   nameServer: { ipAddr: "8.8.8.8", port: 53 },
   * });
   * ```
   *
   * Requires `allow-net` permission.
   *
   * @tags allow-net
   * @category Network
   */
  export function resolveDns(
    query: string,
    recordType: "TXT",
    options?: ResolveDnsOptions,
  ): Promise<string[][]>;

  /**
   * Performs DNS resolution against the given query, returning resolved
   * records.
   *
   * Fails in the cases such as:
   *
   * - the query is in invalid format.
   * - the options have an invalid parameter. For example `nameServer.port` is
   *   beyond the range of 16-bit unsigned integer.
   * - the request timed out.
   *
   * ```ts
   * const a = await Deno.resolveDns("example.com", "A");
   *
   * const aaaa = await Deno.resolveDns("example.com", "AAAA", {
   *   nameServer: { ipAddr: "8.8.8.8", port: 53 },
   * });
   * ```
   *
   * Requires `allow-net` permission.
   *
   * @tags allow-net
   * @category Network
   */
  export function resolveDns(
    query: string,
    recordType: RecordType,
    options?: ResolveDnsOptions,
  ): Promise<
    | string[]
    | CaaRecord[]
    | MxRecord[]
    | NaptrRecord[]
    | SoaRecord[]
    | SrvRecord[]
    | string[][]
  >;

  /**
   * Make the timer of the given `id` block the event loop from finishing.
   *
   * @category Runtime
   */
  export function refTimer(id: number): void;

  /**
   * Make the timer of the given `id` not block the event loop from finishing.
   *
   * @category Runtime
   */
  export function unrefTimer(id: number): void;

  /**
   * Returns the user id of the process on POSIX platforms. Returns null on Windows.
   *
   * ```ts
   * console.log(Deno.uid());
   * ```
   *
   * Requires `allow-sys` permission.
   *
   * @tags allow-sys
   * @category Runtime
   */
  export function uid(): number | null;

  /**
   * Returns the group id of the process on POSIX platforms. Returns null on windows.
   *
   * ```ts
   * console.log(Deno.gid());
   * ```
   *
   * Requires `allow-sys` permission.
   *
   * @tags allow-sys
   * @category Runtime
   */
  export function gid(): number | null;

  /** Additional information for an HTTP request and its connection.
   *
   * @category HTTP Server
   */
  export interface ServeHandlerInfo<Addr extends Deno.Addr = Deno.Addr> {
    /** The remote address of the connection. */
    remoteAddr: Addr;
    /** The completion promise */
    completed: Promise<void>;
  }

  /** A handler for HTTP requests. Consumes a request and returns a response.
   *
   * If a handler throws, the server calling the handler will assume the impact
   * of the error is isolated to the individual request. It will catch the error
   * and if necessary will close the underlying connection.
   *
   * @category HTTP Server
   */
  export type ServeHandler<Addr extends Deno.Addr = Deno.Addr> = (
    request: Request,
    info: ServeHandlerInfo<Addr>,
  ) => Response | Promise<Response>;

  /** Interface that module run with `deno serve` subcommand must conform to.
   *
   * To ensure your code is type-checked properly, make sure to add `satisfies Deno.ServeDefaultExport`
   * to the `export default { ... }` like so:
   *
   * ```ts
   * export default {
   *   fetch(req) {
   *     return new Response("Hello world");
   *   }
   * } satisfies Deno.ServeDefaultExport;
   * ```
   *
   * @category HTTP Server
   */
  export interface ServeDefaultExport {
    /** A handler for HTTP requests. Consumes a request and returns a response.
     *
     * If a handler throws, the server calling the handler will assume the impact
     * of the error is isolated to the individual request. It will catch the error
     * and if necessary will close the underlying connection.
     *
     * @category HTTP Server
     */
    fetch: (
      request: Request,
    ) => Response | Promise<Response>;
  }

  /** Options which can be set when calling {@linkcode Deno.serve}.
   *
   * @category HTTP Server
   */
  export interface ServeOptions<Addr extends Deno.Addr = Deno.Addr> {
    /** An {@linkcode AbortSignal} to close the server and all connections. */
    signal?: AbortSignal;

    /** The handler to invoke when route handlers throw an error. */
    onError?: (error: unknown) => Response | Promise<Response>;

    /** The callback which is called when the server starts listening. */
    onListen?: (localAddr: Addr) => void;
  }

  /**
   * Options that can be passed to `Deno.serve` to create a server listening on
   * a TCP port.
   *
   * @category HTTP Server
   */
  export interface ServeTcpOptions extends ServeOptions<Deno.NetAddr> {
    /** The transport to use. */
    transport?: "tcp";

    /** The port to listen on.
     *
     * Set to `0` to listen on any available port.
     *
     * @default {8000} */
    port?: number;

    /** A literal IP address or host name that can be resolved to an IP address.
     *
     * __Note about `0.0.0.0`__ While listening `0.0.0.0` works on all platforms,
     * the browsers on Windows don't work with the address `0.0.0.0`.
     * You should show the message like `server running on localhost:8080` instead of
     * `server running on 0.0.0.0:8080` if your program supports Windows.
     *
     * @default {"0.0.0.0"} */
    hostname?: string;

    /** Sets `SO_REUSEPORT` on POSIX systems. */
    reusePort?: boolean;
  }

  /**
   * Options that can be passed to `Deno.serve` to create a server listening on
   * a Unix domain socket.
   *
   * @category HTTP Server
   */
  export interface ServeUnixOptions extends ServeOptions<Deno.UnixAddr> {
    /** The transport to use. */
    transport?: "unix";

    /** The unix domain socket path to listen on. */
    path: string;
  }

  /**
   * @category HTTP Server
   */
  export interface ServeInit<Addr extends Deno.Addr = Deno.Addr> {
    /** The handler to invoke to process each incoming request. */
    handler: ServeHandler<Addr>;
  }

  /** An instance of the server created using `Deno.serve()` API.
   *
   * @category HTTP Server
   */
  export interface HttpServer<Addr extends Deno.Addr = Deno.Addr>
    extends AsyncDisposable {
    /** A promise that resolves once server finishes - eg. when aborted using
     * the signal passed to {@linkcode ServeOptions.signal}.
     */
    finished: Promise<void>;

    /** The local address this server is listening on. */
    addr: Addr;

    /**
     * Make the server block the event loop from finishing.
     *
     * Note: the server blocks the event loop from finishing by default.
     * This method is only meaningful after `.unref()` is called.
     */
    ref(): void;

    /** Make the server not block the event loop from finishing. */
    unref(): void;

    /** Gracefully close the server. No more new connections will be accepted,
     * while pending requests will be allowed to finish.
     */
    shutdown(): Promise<void>;
  }

  /** Serves HTTP requests with the given handler.
   *
   * The below example serves with the port `8000` on hostname `"127.0.0.1"`.
   *
   * ```ts
   * Deno.serve((_req) => new Response("Hello, world"));
   * ```
   *
   * @category HTTP Server
   */
  export function serve(
    handler: ServeHandler<Deno.NetAddr>,
  ): HttpServer<Deno.NetAddr>;
  /** Serves HTTP requests with the given option bag and handler.
   *
   * You can specify the socket path with `path` option.
   *
   * ```ts
   * Deno.serve(
   *   { path: "path/to/socket" },
   *   (_req) => new Response("Hello, world")
   * );
   * ```
   *
   * You can stop the server with an {@linkcode AbortSignal}. The abort signal
   * needs to be passed as the `signal` option in the options bag. The server
   * aborts when the abort signal is aborted. To wait for the server to close,
   * await the promise returned from the `Deno.serve` API.
   *
   * ```ts
   * const ac = new AbortController();
   *
   * const server = Deno.serve(
   *    { signal: ac.signal, path: "path/to/socket" },
   *    (_req) => new Response("Hello, world")
   * );
   * server.finished.then(() => console.log("Server closed"));
   *
   * console.log("Closing server...");
   * ac.abort();
   * ```
   *
   * By default `Deno.serve` prints the message
   * `Listening on path/to/socket` on listening. If you like to
   * change this behavior, you can specify a custom `onListen` callback.
   *
   * ```ts
   * Deno.serve({
   *   onListen({ path }) {
   *     console.log(`Server started at ${path}`);
   *     // ... more info specific to your server ..
   *   },
   *   path: "path/to/socket",
   * }, (_req) => new Response("Hello, world"));
   * ```
   *
   * @category HTTP Server
   */
  export function serve(
    options: ServeUnixOptions,
    handler: ServeHandler<Deno.UnixAddr>,
  ): HttpServer<Deno.UnixAddr>;
  /** Serves HTTP requests with the given option bag and handler.
   *
   * You can specify an object with a port and hostname option, which is the
   * address to listen on. The default is port `8000` on hostname `"0.0.0.0"`.
   *
   * You can change the address to listen on using the `hostname` and `port`
   * options. The below example serves on port `3000` and hostname `"127.0.0.1"`.
   *
   * ```ts
   * Deno.serve(
   *   { port: 3000, hostname: "127.0.0.1" },
   *   (_req) => new Response("Hello, world")
   * );
   * ```
   *
   * You can stop the server with an {@linkcode AbortSignal}. The abort signal
   * needs to be passed as the `signal` option in the options bag. The server
   * aborts when the abort signal is aborted. To wait for the server to close,
   * await the promise returned from the `Deno.serve` API.
   *
   * ```ts
   * const ac = new AbortController();
   *
   * const server = Deno.serve(
   *    { signal: ac.signal },
   *    (_req) => new Response("Hello, world")
   * );
   * server.finished.then(() => console.log("Server closed"));
   *
   * console.log("Closing server...");
   * ac.abort();
   * ```
   *
   * By default `Deno.serve` prints the message
   * `Listening on http://<hostname>:<port>/` on listening. If you like to
   * change this behavior, you can specify a custom `onListen` callback.
   *
   * ```ts
   * Deno.serve({
   *   onListen({ port, hostname }) {
   *     console.log(`Server started at http://${hostname}:${port}`);
   *     // ... more info specific to your server ..
   *   },
   * }, (_req) => new Response("Hello, world"));
   * ```
   *
   * To enable TLS you must specify the `key` and `cert` options.
   *
   * ```ts
   * const cert = "-----BEGIN CERTIFICATE-----\n...\n-----END CERTIFICATE-----\n";
   * const key = "-----BEGIN PRIVATE KEY-----\n...\n-----END PRIVATE KEY-----\n";
   * Deno.serve({ cert, key }, (_req) => new Response("Hello, world"));
   * ```
   *
   * @category HTTP Server
   */
  export function serve(
    options:
      | ServeTcpOptions
      | (ServeTcpOptions & TlsCertifiedKeyOptions),
    handler: ServeHandler<Deno.NetAddr>,
  ): HttpServer<Deno.NetAddr>;
  /** Serves HTTP requests with the given option bag.
   *
   * You can specify an object with the path option, which is the
   * unix domain socket to listen on.
   *
   * ```ts
   * const ac = new AbortController();
   *
   * const server = Deno.serve({
   *   path: "path/to/socket",
   *   handler: (_req) => new Response("Hello, world"),
   *   signal: ac.signal,
   *   onListen({ path }) {
   *     console.log(`Server started at ${path}`);
   *   },
   * });
   * server.finished.then(() => console.log("Server closed"));
   *
   * console.log("Closing server...");
   * ac.abort();
   * ```
   *
   * @category HTTP Server
   */
  export function serve(
    options: ServeUnixOptions & ServeInit<Deno.UnixAddr>,
  ): HttpServer<Deno.UnixAddr>;
  /** Serves HTTP requests with the given option bag.
   *
   * You can specify an object with a port and hostname option, which is the
   * address to listen on. The default is port `8000` on hostname `"0.0.0.0"`.
   *
   * ```ts
   * const ac = new AbortController();
   *
   * const server = Deno.serve({
   *   port: 3000,
   *   hostname: "127.0.0.1",
   *   handler: (_req) => new Response("Hello, world"),
   *   signal: ac.signal,
   *   onListen({ port, hostname }) {
   *     console.log(`Server started at http://${hostname}:${port}`);
   *   },
   * });
   * server.finished.then(() => console.log("Server closed"));
   *
   * console.log("Closing server...");
   * ac.abort();
   * ```
   *
   * @category HTTP Server
   */
  export function serve(
    options:
      & (ServeTcpOptions | (ServeTcpOptions & TlsCertifiedKeyOptions))
      & ServeInit<Deno.NetAddr>,
  ): HttpServer<Deno.NetAddr>;

  /** All plain number types for interfacing with foreign functions.
   *
   * @category FFI
   */
  export type NativeNumberType =
    | "u8"
    | "i8"
    | "u16"
    | "i16"
    | "u32"
    | "i32"
    | "f32"
    | "f64";

  /** All BigInt number types for interfacing with foreign functions.
   *
   * @category FFI
   */
  export type NativeBigIntType =
    | "u64"
    | "i64"
    | "usize"
    | "isize";

  /** The native boolean type for interfacing to foreign functions.
   *
   * @category FFI
   */
  export type NativeBooleanType = "bool";

  /** The native pointer type for interfacing to foreign functions.
   *
   * @category FFI
   */
  export type NativePointerType = "pointer";

  /** The native buffer type for interfacing to foreign functions.
   *
   * @category FFI
   */
  export type NativeBufferType = "buffer";

  /** The native function type for interfacing with foreign functions.
   *
   * @category FFI
   */
  export type NativeFunctionType = "function";

  /** The native void type for interfacing with foreign functions.
   *
   * @category FFI
   */
  export type NativeVoidType = "void";

  /** The native struct type for interfacing with foreign functions.
   *
   * @category FFI
   */
  export type NativeStructType = { readonly struct: readonly NativeType[] };

  /**
   * @category FFI
   */
  export const brand: unique symbol;

  /**
   * @category FFI
   */
  export type NativeU8Enum<T extends number> = "u8" & { [brand]: T };
  /**
   * @category FFI
   */
  export type NativeI8Enum<T extends number> = "i8" & { [brand]: T };
  /**
   * @category FFI
   */
  export type NativeU16Enum<T extends number> = "u16" & { [brand]: T };
  /**
   * @category FFI
   */
  export type NativeI16Enum<T extends number> = "i16" & { [brand]: T };
  /**
   * @category FFI
   */
  export type NativeU32Enum<T extends number> = "u32" & { [brand]: T };
  /**
   * @category FFI
   */
  export type NativeI32Enum<T extends number> = "i32" & { [brand]: T };
  /**
   * @category FFI
   */
  export type NativeTypedPointer<T extends PointerObject> = "pointer" & {
    [brand]: T;
  };
  /**
   * @category FFI
   */
  export type NativeTypedFunction<T extends UnsafeCallbackDefinition> =
    & "function"
    & {
      [brand]: T;
    };

  /** All supported types for interfacing with foreign functions.
   *
   * @category FFI
   */
  export type NativeType =
    | NativeNumberType
    | NativeBigIntType
    | NativeBooleanType
    | NativePointerType
    | NativeBufferType
    | NativeFunctionType
    | NativeStructType;

  /** @category FFI
   */
  export type NativeResultType = NativeType | NativeVoidType;

  /** Type conversion for foreign symbol parameters and unsafe callback return
   * types.
   *
   * @category FFI
   */
  export type ToNativeType<T extends NativeType = NativeType> = T extends
    NativeStructType ? BufferSource
    : T extends NativeNumberType ? T extends NativeU8Enum<infer U> ? U
      : T extends NativeI8Enum<infer U> ? U
      : T extends NativeU16Enum<infer U> ? U
      : T extends NativeI16Enum<infer U> ? U
      : T extends NativeU32Enum<infer U> ? U
      : T extends NativeI32Enum<infer U> ? U
      : number
    : T extends NativeBigIntType ? bigint
    : T extends NativeBooleanType ? boolean
    : T extends NativePointerType
      ? T extends NativeTypedPointer<infer U> ? U | null : PointerValue
    : T extends NativeFunctionType
      ? T extends NativeTypedFunction<infer U> ? PointerValue<U> | null
      : PointerValue
    : T extends NativeBufferType ? BufferSource | null
    : never;

  /** Type conversion for unsafe callback return types.
   *
   * @category FFI
   */
  export type ToNativeResultType<
    T extends NativeResultType = NativeResultType,
  > = T extends NativeStructType ? BufferSource
    : T extends NativeNumberType ? T extends NativeU8Enum<infer U> ? U
      : T extends NativeI8Enum<infer U> ? U
      : T extends NativeU16Enum<infer U> ? U
      : T extends NativeI16Enum<infer U> ? U
      : T extends NativeU32Enum<infer U> ? U
      : T extends NativeI32Enum<infer U> ? U
      : number
    : T extends NativeBigIntType ? bigint
    : T extends NativeBooleanType ? boolean
    : T extends NativePointerType
      ? T extends NativeTypedPointer<infer U> ? U | null : PointerValue
    : T extends NativeFunctionType
      ? T extends NativeTypedFunction<infer U> ? PointerObject<U> | null
      : PointerValue
    : T extends NativeBufferType ? BufferSource | null
    : T extends NativeVoidType ? void
    : never;

  /** A utility type for conversion of parameter types of foreign functions.
   *
   * @category FFI
   */
  export type ToNativeParameterTypes<T extends readonly NativeType[]> =
    //
    [(T[number])[]] extends [T] ? ToNativeType<T[number]>[]
      : [readonly (T[number])[]] extends [T]
        ? readonly ToNativeType<T[number]>[]
      : T extends readonly [...NativeType[]] ? {
          [K in keyof T]: ToNativeType<T[K]>;
        }
      : never;

  /** Type conversion for foreign symbol return types and unsafe callback
   * parameters.
   *
   * @category FFI
   */
  export type FromNativeType<T extends NativeType = NativeType> = T extends
    NativeStructType ? Uint8Array
    : T extends NativeNumberType ? T extends NativeU8Enum<infer U> ? U
      : T extends NativeI8Enum<infer U> ? U
      : T extends NativeU16Enum<infer U> ? U
      : T extends NativeI16Enum<infer U> ? U
      : T extends NativeU32Enum<infer U> ? U
      : T extends NativeI32Enum<infer U> ? U
      : number
    : T extends NativeBigIntType ? bigint
    : T extends NativeBooleanType ? boolean
    : T extends NativePointerType
      ? T extends NativeTypedPointer<infer U> ? U | null : PointerValue
    : T extends NativeBufferType ? PointerValue
    : T extends NativeFunctionType
      ? T extends NativeTypedFunction<infer U> ? PointerObject<U> | null
      : PointerValue
    : never;

  /** Type conversion for foreign symbol return types.
   *
   * @category FFI
   */
  export type FromNativeResultType<
    T extends NativeResultType = NativeResultType,
  > = T extends NativeStructType ? Uint8Array
    : T extends NativeNumberType ? T extends NativeU8Enum<infer U> ? U
      : T extends NativeI8Enum<infer U> ? U
      : T extends NativeU16Enum<infer U> ? U
      : T extends NativeI16Enum<infer U> ? U
      : T extends NativeU32Enum<infer U> ? U
      : T extends NativeI32Enum<infer U> ? U
      : number
    : T extends NativeBigIntType ? bigint
    : T extends NativeBooleanType ? boolean
    : T extends NativePointerType
      ? T extends NativeTypedPointer<infer U> ? U | null : PointerValue
    : T extends NativeBufferType ? PointerValue
    : T extends NativeFunctionType
      ? T extends NativeTypedFunction<infer U> ? PointerObject<U> | null
      : PointerValue
    : T extends NativeVoidType ? void
    : never;

  /** @category FFI
   */
  export type FromNativeParameterTypes<
    T extends readonly NativeType[],
  > =
    //
    [(T[number])[]] extends [T] ? FromNativeType<T[number]>[]
      : [readonly (T[number])[]] extends [T]
        ? readonly FromNativeType<T[number]>[]
      : T extends readonly [...NativeType[]] ? {
          [K in keyof T]: FromNativeType<T[K]>;
        }
      : never;

  /** The interface for a foreign function as defined by its parameter and result
   * types.
   *
   * @category FFI
   */
  export interface ForeignFunction<
    Parameters extends readonly NativeType[] = readonly NativeType[],
    Result extends NativeResultType = NativeResultType,
    NonBlocking extends boolean = boolean,
  > {
    /** Name of the symbol.
     *
     * Defaults to the key name in symbols object. */
    name?: string;
    /** The parameters of the foreign function. */
    parameters: Parameters;
    /** The result (return value) of the foreign function. */
    result: Result;
    /** When `true`, function calls will run on a dedicated blocking thread and
     * will return a `Promise` resolving to the `result`. */
    nonblocking?: NonBlocking;
    /** When `true`, dlopen will not fail if the symbol is not found.
     * Instead, the symbol will be set to `null`.
     *
     * @default {false} */
    optional?: boolean;
  }

  /** @category FFI
   */
  export interface ForeignStatic<Type extends NativeType = NativeType> {
    /** Name of the symbol, defaults to the key name in symbols object. */
    name?: string;
    /** The type of the foreign static value. */
    type: Type;
    /** When `true`, dlopen will not fail if the symbol is not found.
     * Instead, the symbol will be set to `null`.
     *
     * @default {false} */
    optional?: boolean;
  }

  /** A foreign library interface descriptor.
   *
   * @category FFI
   */
  export interface ForeignLibraryInterface {
    [name: string]: ForeignFunction | ForeignStatic;
  }

  /** A utility type that infers a foreign symbol.
   *
   * @category FFI
   */
  export type StaticForeignSymbol<T extends ForeignFunction | ForeignStatic> =
    T extends ForeignFunction ? FromForeignFunction<T>
      : T extends ForeignStatic ? FromNativeType<T["type"]>
      : never;

  /**  @category FFI
   */
  export type FromForeignFunction<T extends ForeignFunction> =
    T["parameters"] extends readonly [] ? () => StaticForeignSymbolReturnType<T>
      : (
        ...args: ToNativeParameterTypes<T["parameters"]>
      ) => StaticForeignSymbolReturnType<T>;

  /** @category FFI
   */
  export type StaticForeignSymbolReturnType<T extends ForeignFunction> =
    ConditionalAsync<T["nonblocking"], FromNativeResultType<T["result"]>>;

  /** @category FFI
   */
  export type ConditionalAsync<IsAsync extends boolean | undefined, T> =
    IsAsync extends true ? Promise<T> : T;

  /** A utility type that infers a foreign library interface.
   *
   * @category FFI
   */
  export type StaticForeignLibraryInterface<T extends ForeignLibraryInterface> =
    {
      [K in keyof T]: T[K]["optional"] extends true
        ? StaticForeignSymbol<T[K]> | null
        : StaticForeignSymbol<T[K]>;
    };

  /** A non-null pointer, represented as an object
   * at runtime. The object's prototype is `null`
   * and cannot be changed. The object cannot be
   * assigned to either and is thus entirely read-only.
   *
   * To interact with memory through a pointer use the
   * {@linkcode UnsafePointerView} class. To create a
   * pointer from an address or the get the address of
   * a pointer use the static methods of the
   * {@linkcode UnsafePointer} class.
   *
   * @category FFI
   */
  export type PointerObject<T = unknown> = { [brand]: T };

  /** Pointers are represented either with a {@linkcode PointerObject}
   * object or a `null` if the pointer is null.
   *
   * @category FFI
   */
  export type PointerValue<T = unknown> = null | PointerObject<T>;

  /** A collection of static functions for interacting with pointer objects.
   *
   * @category FFI
   */
  export class UnsafePointer {
    /** Create a pointer from a numeric value. This one is <i>really</i> dangerous! */
    static create<T = unknown>(value: bigint): PointerValue<T>;
    /** Returns `true` if the two pointers point to the same address. */
    static equals<T = unknown>(a: PointerValue<T>, b: PointerValue<T>): boolean;
    /** Return the direct memory pointer to the typed array in memory. */
    static of<T = unknown>(
      value: Deno.UnsafeCallback | BufferSource,
    ): PointerValue<T>;
    /** Return a new pointer offset from the original by `offset` bytes. */
    static offset<T = unknown>(
      value: PointerObject,
      offset: number,
    ): PointerValue<T>;
    /** Get the numeric value of a pointer */
    static value(value: PointerValue): bigint;
  }

  /** An unsafe pointer view to a memory location as specified by the `pointer`
   * value. The `UnsafePointerView` API follows the standard built in interface
   * {@linkcode DataView} for accessing the underlying types at an memory
   * location (numbers, strings and raw bytes).
   *
   * @category FFI
   */
  export class UnsafePointerView {
    constructor(pointer: PointerObject);

    pointer: PointerObject;

    /** Gets a boolean at the specified byte offset from the pointer. */
    getBool(offset?: number): boolean;
    /** Gets an unsigned 8-bit integer at the specified byte offset from the
     * pointer. */
    getUint8(offset?: number): number;
    /** Gets a signed 8-bit integer at the specified byte offset from the
     * pointer. */
    getInt8(offset?: number): number;
    /** Gets an unsigned 16-bit integer at the specified byte offset from the
     * pointer. */
    getUint16(offset?: number): number;
    /** Gets a signed 16-bit integer at the specified byte offset from the
     * pointer. */
    getInt16(offset?: number): number;
    /** Gets an unsigned 32-bit integer at the specified byte offset from the
     * pointer. */
    getUint32(offset?: number): number;
    /** Gets a signed 32-bit integer at the specified byte offset from the
     * pointer. */
    getInt32(offset?: number): number;
    /** Gets an unsigned 64-bit integer at the specified byte offset from the
     * pointer. */
    getBigUint64(offset?: number): bigint;
    /** Gets a signed 64-bit integer at the specified byte offset from the
     * pointer. */
    getBigInt64(offset?: number): bigint;
    /** Gets a signed 32-bit float at the specified byte offset from the
     * pointer. */
    getFloat32(offset?: number): number;
    /** Gets a signed 64-bit float at the specified byte offset from the
     * pointer. */
    getFloat64(offset?: number): number;
    /** Gets a pointer at the specified byte offset from the pointer */
    getPointer<T = unknown>(offset?: number): PointerValue<T>;
    /** Gets a C string (`null` terminated string) at the specified byte offset
     * from the pointer. */
    getCString(offset?: number): string;
    /** Gets a C string (`null` terminated string) at the specified byte offset
     * from the specified pointer. */
    static getCString(
      pointer: PointerObject,
      offset?: number,
    ): string;
    /** Gets an `ArrayBuffer` of length `byteLength` at the specified byte
     * offset from the pointer. */
    getArrayBuffer(byteLength: number, offset?: number): ArrayBuffer;
    /** Gets an `ArrayBuffer` of length `byteLength` at the specified byte
     * offset from the specified pointer. */
    static getArrayBuffer(
      pointer: PointerObject,
      byteLength: number,
      offset?: number,
    ): ArrayBuffer;
    /** Copies the memory of the pointer into a typed array.
     *
     * Length is determined from the typed array's `byteLength`.
     *
     * Also takes optional byte offset from the pointer. */
    copyInto(destination: BufferSource, offset?: number): void;
    /** Copies the memory of the specified pointer into a typed array.
     *
     * Length is determined from the typed array's `byteLength`.
     *
     * Also takes optional byte offset from the pointer. */
    static copyInto(
      pointer: PointerObject,
      destination: BufferSource,
      offset?: number,
    ): void;
  }

  /** An unsafe pointer to a function, for calling functions that are not present
   * as symbols.
   *
   * @category FFI
   */
  export class UnsafeFnPointer<const Fn extends ForeignFunction> {
    /** The pointer to the function. */
    pointer: PointerObject<Fn>;
    /** The definition of the function. */
    definition: Fn;

    constructor(pointer: PointerObject<NoInfer<Fn>>, definition: Fn);
    /** @deprecated Properly type {@linkcode pointer} using {@linkcode NativeTypedFunction} or {@linkcode UnsafeCallbackDefinition} types. */
    constructor(pointer: PointerObject, definition: Fn);

    /** Call the foreign function. */
    call: FromForeignFunction<Fn>;
  }

  /** Definition of a unsafe callback function.
   *
   * @category FFI
   */
  export interface UnsafeCallbackDefinition<
    Parameters extends readonly NativeType[] = readonly NativeType[],
    Result extends NativeResultType = NativeResultType,
  > {
    /** The parameters of the callbacks. */
    parameters: Parameters;
    /** The current result of the callback. */
    result: Result;
  }

  /** An unsafe callback function.
   *
   * @category FFI
   */
  export type UnsafeCallbackFunction<
    Parameters extends readonly NativeType[] = readonly NativeType[],
    Result extends NativeResultType = NativeResultType,
  > = Parameters extends readonly [] ? () => ToNativeResultType<Result> : (
    ...args: FromNativeParameterTypes<Parameters>
  ) => ToNativeResultType<Result>;

  /** An unsafe function pointer for passing JavaScript functions as C function
   * pointers to foreign function calls.
   *
   * The function pointer remains valid until the `close()` method is called.
   *
   * All `UnsafeCallback` are always thread safe in that they can be called from
   * foreign threads without crashing. However, they do not wake up the Deno event
   * loop by default.
   *
   * If a callback is to be called from foreign threads, use the `threadSafe()`
   * static constructor or explicitly call `ref()` to have the callback wake up
   * the Deno event loop when called from foreign threads. This also stops
   * Deno's process from exiting while the callback still exists and is not
   * unref'ed.
   *
   * Use `deref()` to then allow Deno's process to exit. Calling `deref()` on
   * a ref'ed callback does not stop it from waking up the Deno event loop when
   * called from foreign threads.
   *
   * @category FFI
   */
  export class UnsafeCallback<
    const Definition extends UnsafeCallbackDefinition =
      UnsafeCallbackDefinition,
  > {
    constructor(
      definition: Definition,
      callback: UnsafeCallbackFunction<
        Definition["parameters"],
        Definition["result"]
      >,
    );

    /** The pointer to the unsafe callback. */
    readonly pointer: PointerObject<Definition>;
    /** The definition of the unsafe callback. */
    readonly definition: Definition;
    /** The callback function. */
    readonly callback: UnsafeCallbackFunction<
      Definition["parameters"],
      Definition["result"]
    >;

    /**
     * Creates an {@linkcode UnsafeCallback} and calls `ref()` once to allow it to
     * wake up the Deno event loop when called from foreign threads.
     *
     * This also stops Deno's process from exiting while the callback still
     * exists and is not unref'ed.
     */
    static threadSafe<
      Definition extends UnsafeCallbackDefinition = UnsafeCallbackDefinition,
    >(
      definition: Definition,
      callback: UnsafeCallbackFunction<
        Definition["parameters"],
        Definition["result"]
      >,
    ): UnsafeCallback<Definition>;

    /**
     * Increments the callback's reference counting and returns the new
     * reference count.
     *
     * After `ref()` has been called, the callback always wakes up the
     * Deno event loop when called from foreign threads.
     *
     * If the callback's reference count is non-zero, it keeps Deno's
     * process from exiting.
     */
    ref(): number;

    /**
     * Decrements the callback's reference counting and returns the new
     * reference count.
     *
     * Calling `unref()` does not stop a callback from waking up the Deno
     * event loop when called from foreign threads.
     *
     * If the callback's reference counter is zero, it no longer keeps
     * Deno's process from exiting.
     */
    unref(): number;

    /**
     * Removes the C function pointer associated with this instance.
     *
     * Continuing to use the instance or the C function pointer after closing
     * the `UnsafeCallback` will lead to errors and crashes.
     *
     * Calling this method sets the callback's reference counting to zero,
     * stops the callback from waking up the Deno event loop when called from
     * foreign threads and no longer keeps Deno's process from exiting.
     */
    close(): void;
  }

  /** A dynamic library resource.  Use {@linkcode Deno.dlopen} to load a dynamic
   * library and return this interface.
   *
   * @category FFI
   */
  export interface DynamicLibrary<S extends ForeignLibraryInterface> {
    /** All of the registered library along with functions for calling them. */
    symbols: StaticForeignLibraryInterface<S>;
    /** Removes the pointers associated with the library symbols.
     *
     * Continuing to use symbols that are part of the library will lead to
     * errors and crashes.
     *
     * Calling this method will also immediately set any references to zero and
     * will no longer keep Deno's process from exiting.
     */
    close(): void;
  }

  /** Opens an external dynamic library and registers symbols, making foreign
   * functions available to be called.
   *
   * Requires `allow-ffi` permission. Loading foreign dynamic libraries can in
   * theory bypass all of the sandbox permissions. While it is a separate
   * permission users should acknowledge in practice that is effectively the
   * same as running with the `allow-all` permission.
   *
   * @example Given a C library which exports a foreign function named `add()`
   *
   * ```ts
   * // Determine library extension based on
   * // your OS.
   * let libSuffix = "";
   * switch (Deno.build.os) {
   *   case "windows":
   *     libSuffix = "dll";
   *     break;
   *   case "darwin":
   *     libSuffix = "dylib";
   *     break;
   *   default:
   *     libSuffix = "so";
   *     break;
   * }
   *
   * const libName = `./libadd.${libSuffix}`;
   * // Open library and define exported symbols
   * const dylib = Deno.dlopen(
   *   libName,
   *   {
   *     "add": { parameters: ["isize", "isize"], result: "isize" },
   *   } as const,
   * );
   *
   * // Call the symbol `add`
   * const result = dylib.symbols.add(35n, 34n); // 69n
   *
   * console.log(`Result from external addition of 35 and 34: ${result}`);
   * ```
   *
   * @tags allow-ffi
   * @category FFI
   */
  export function dlopen<const S extends ForeignLibraryInterface>(
    filename: string | URL,
    symbols: S,
  ): DynamicLibrary<S>;
}