笔记03 Deno
Deno
1 控制台打印
// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
console.log("Welcome to Deno 🦕");C:\Users\Administrator
λ deno run https://deno.land/std/examples/welcome.ts
Download https://deno.land/std/examples/welcome.ts
Warning Implicitly using latest version (0.73.0) for https://deno.land/std/examples/welcome.ts
Download https://deno.land/std@0.73.0/examples/welcome.ts
Check https://deno.land/std@0.73.0/examples/welcome.ts
Welcome to Deno �2 发出一个 HTTP 请求
// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
const url_ = Deno.args[0];
const res = await fetch(url_);
// TODO(ry) Re-enable streaming in this example.
// Originally we did: await Deno.copy(res.body, Deno.stdout);
// But maybe more JS-y would be: res.pipeTo(Deno.stdout);
const body = new Uint8Array(await res.arrayBuffer());
await Deno.stdout.write(body);C:\Users\Administrator
λ deno run https://deno.land/std/examples/curl.ts https://example.com
Download https://deno.land/std/examples/curl.ts
Warning Implicitly using latest version (0.73.0) for https://deno.land/std/examples/curl.ts
Download https://deno.land/std@0.73.0/examples/curl.ts
Check https://deno.land/std@0.73.0/examples/curl.ts
error: Uncaught PermissionDenied: network access to "https://example.com/", run again with the --allow-net flag
at Object.jsonOpAsync (core.js:236:13)
at async fetch (deno:op_crates/fetch/26_fetch.js:1272:29)
at async https://deno.land/std@0.73.0/examples/curl.ts:3:13C:\Users\Administrator
λ deno run --allow-net=example.com https://deno.land/std/examples/curl.ts https://example.com
<!doctype html>
<html>
<head>
<title>Example Domain</title>
<meta charset="utf-8" />
<meta http-equiv="Content-type" content="text/html; charset=utf-8" />
<meta name="viewport" content="width=device-width, initial-scale=1" />
<style type="text/css">
body {
background-color: #f0f0f2;
margin: 0;
padding: 0;
font-family: -apple-system, system-ui, BlinkMacSystemFont, "Segoe UI", "Open Sans", "Helvetica Neue", Helvetica, Arial, sans-serif;
}
div {
width: 600px;
margin: 5em auto;
padding: 2em;
background-color: #fdfdff;
border-radius: 0.5em;
box-shadow: 2px 3px 7px 2px rgba(0,0,0,0.02);
}
a:link, a:visited {
color: #38488f;
text-decoration: none;
}
@media (max-width: 700px) {
div {
margin: 0 auto;
width: auto;
}
}
</style>
</head>
<body>
<div>
<h1>Example Domain</h1>
<p>This domain is for use in illustrative examples in documents. You may use this
domain in literature without prior coordination or asking for permission.</p>
<p><a href="https://www.iana.org/domains/example">More information...</a></p>
</div>
</body> 3 读取一个文件
// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
const filenames = Deno.args;
for (const filename of filenames) {
const file = await Deno.open(filename);
await Deno.copy(file, Deno.stdout);
file.close();
}C:\Users\Administrator
λ deno run --allow-read https://deno.land/std/examples/cat.ts /etc/passwd
Download https://deno.land/std/examples/cat.ts
Warning Implicitly using latest version (0.73.0) for https://deno.land/std/examples/cat.ts
Download https://deno.land/std@0.73.0/examples/cat.ts
Check https://deno.land/std@0.73.0/examples/cat.ts
error: Uncaught NotFound: 系统找不到指定的路径。 (os error 3)
at Object.jsonOpAsync (core.js:236:13)
at async Object.open (deno:cli/rt/30_files.js:44:17)
at async https://deno.land/std@0.73.0/examples/cat.ts:4:16