diff --git a/buffer.ts b/buffer.ts
index ba2715cef7..d177bc18dc 100644
--- a/buffer.ts
+++ b/buffer.ts
@@ -120,10 +120,7 @@ export class Buffer implements Reader, Writer {
    * is drained. The return value n is the number of bytes read. If the
    * buffer has no data to return, eof in the response will be true.
    */
-  async read(p: ArrayBufferView): Promise<ReadResult> {
-    if (!(p instanceof Uint8Array)) {
-      throw Error("Only Uint8Array supported");
-    }
+  async read(p: Uint8Array): Promise<ReadResult> {
     if (this.empty()) {
       // Buffer is empty, reset to recover space.
       this.reset();
@@ -139,11 +136,8 @@ export class Buffer implements Reader, Writer {
     return { nread, eof: false };
   }
 
-  async write(p: ArrayBufferView): Promise<number> {
+  async write(p: Uint8Array): Promise<number> {
     const m = this._grow(p.byteLength);
-    if (!(p instanceof Uint8Array)) {
-      throw Error("Only Uint8Array supported");
-    }
     return copyBytes(this.buf, p, m);
   }
 
diff --git a/bufio_test.ts b/bufio_test.ts
index f3430a755b..5f32500a7a 100644
--- a/bufio_test.ts
+++ b/bufio_test.ts
@@ -159,7 +159,7 @@ const testOutput = encoder.encode("0123456789abcdefghijklmnopqrstuvwxy");
 class TestReader implements Reader {
   constructor(private data: Uint8Array, private stride: number) {}
 
-  async read(buf: ArrayBufferView): Promise<ReadResult> {
+  async read(buf: Uint8Array): Promise<ReadResult> {
     let nread = this.stride;
     if (nread > this.data.byteLength) {
       nread = this.data.byteLength;
diff --git a/http_test.ts b/http_test.ts
index b0007a8927..e6cb87f01e 100644
--- a/http_test.ts
+++ b/http_test.ts
@@ -5,7 +5,8 @@ const addr = "0.0.0.0:8000";
 const s = serve(addr);
 console.log(`listening on http://${addr}/`);
 
-const body = new TextEncoder().encode("Hello World\n");
+const body = (new TextEncoder()).encode("Hello World\n");
+
 
 async function main() {
   for await (const req of s) {
diff --git a/iotest.ts b/iotest.ts
index e2498e1557..e3a42f58a2 100644
--- a/iotest.ts
+++ b/iotest.ts
@@ -11,7 +11,7 @@ import { Reader, ReadResult } from "deno";
 export class OneByteReader implements Reader {
   constructor(readonly r: Reader) {}
 
-  async read(p: ArrayBufferView): Promise<ReadResult> {
+  async read(p: Uint8Array): Promise<ReadResult> {
     if (p.byteLength === 0) {
       return { nread: 0, eof: false };
     }
@@ -28,7 +28,7 @@ export class OneByteReader implements Reader {
 export class HalfReader implements Reader {
   constructor(readonly r: Reader) {}
 
-  async read(p: ArrayBufferView): Promise<ReadResult> {
+  async read(p: Uint8Array): Promise<ReadResult> {
     if (!(p instanceof Uint8Array)) {
       throw Error("expected Uint8Array");
     }
@@ -51,7 +51,7 @@ export class TimeoutReader implements Reader {
   count = 0;
   constructor(readonly r: Reader) {}
 
-  async read(p: ArrayBufferView): Promise<ReadResult> {
+  async read(p: Uint8Array): Promise<ReadResult> {
     this.count++;
     if (this.count === 2) {
       throw new ErrTimeout();