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authorRyan Dahl <ry@tinyclouds.org>2019-10-10 05:31:23 -0400
committerGitHub <noreply@github.com>2019-10-10 05:31:23 -0400
commite7562eed8c816cd0d97aab6b818d7c8453dbaa2b (patch)
treec5a9f536e79d2c8d2d02897511a9138acaf35394 /std/io/writers.ts
parent3882c9d19a641e0c919f1350d87c6d7ee280cf78 (diff)
parent93f7f00c956c14620ef031626f124b57397ca867 (diff)
Merge deno_std in main repo (#3091)
The history of deno_std is persevered but rewritten to update links to issues and PRs Fixes denoland/deno_std#603
Diffstat (limited to 'std/io/writers.ts')
m---------std0
-rw-r--r--std/io/writers.ts37
2 files changed, 37 insertions, 0 deletions
diff --git a/std b/std
deleted file mode 160000
-Subproject 43aafbf33285753e7b42230f0eb7969b300f71c
diff --git a/std/io/writers.ts b/std/io/writers.ts
new file mode 100644
index 000000000..91d19a9d7
--- /dev/null
+++ b/std/io/writers.ts
@@ -0,0 +1,37 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+type Writer = Deno.Writer;
+import { decode, encode } from "../strings/mod.ts";
+
+/** Writer utility for buffering string chunks */
+export class StringWriter implements Writer {
+ private chunks: Uint8Array[] = [];
+ private byteLength = 0;
+ private cache: string | undefined;
+
+ constructor(private base: string = "") {
+ const c = encode(base);
+ this.chunks.push(c);
+ this.byteLength += c.byteLength;
+ }
+
+ async write(p: Uint8Array): Promise<number> {
+ this.chunks.push(p);
+ this.byteLength += p.byteLength;
+ this.cache = undefined;
+ return p.byteLength;
+ }
+
+ toString(): string {
+ if (this.cache) {
+ return this.cache;
+ }
+ const buf = new Uint8Array(this.byteLength);
+ let offs = 0;
+ for (const chunk of this.chunks) {
+ buf.set(chunk, offs);
+ offs += chunk.byteLength;
+ }
+ this.cache = decode(buf);
+ return this.cache!;
+ }
+}