Acorn工具 - 模具行业Web开发参考——模具行业从业者必备知识手册

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<h2>Acorn</h2>

A tiny, fast JavaScript parser written in JavaScript.

<h3>Community</h3>

Acorn is open source software released under an
<a href="https://github.com/acornjs/acorn/blob/master/acorn/LICENSE">MIT license</a>.

You are welcome to
<a href="https://github.com/acornjs/acorn/issues">report bugs</a> or create pull
requests on <a href="https://github.com/acornjs/acorn">github</a>.

<h3>Installation</h3>

The easiest way to install acorn is from <a href="https://www.npmjs.com/"><code>npm</code></a>:

<pre><code>
npm install acorn
</code></pre>

Alternately, you can download the source and build acorn yourself:

<pre><code>
git clone https://github.com/acornjs/acorn.git
cd acorn
npm install
</code></pre>
<h3>Importing acorn</h3>

ESM as well as CommonJS is supported for all 3: <code>acorn</code>, <code>acorn-walk</code> and <code>acorn-loose</code>.

ESM example for <code>acorn</code>:

<pre><code>
import * as acorn from "acorn"
</code></pre>

CommonJS example for <code>acorn</code>:

<pre><code>
let acorn = require("acorn")
</code></pre>

ESM is preferred, as it allows better editor auto-completions by offering TypeScript support.
For this reason, following examples will use ESM imports.

<h3>Interface</h3>

parse<code>(input, options)</code> is the main interface to the library. The
<code>input</code> parameter is a string, <code>options</code> must be an object setting
some of the options listed below. The return value will be an abstract
syntax tree object as specified by the ESTree
spec.

<pre><code>
import * as acorn from "acorn"
console.log(acorn.parse("1 + 1", {ecmaVersion: 2020}))
</code></pre>

When encountering a syntax error, the parser will raise a
<code>SyntaxError</code> object with a meaningful message. The error object will
have a <code>pos</code> property that indicates the string offset at which the
error occurred, and a <code>loc</code> object that contains a <code>{line, column}</code>
object referring to that same position.

Options are provided by in a second argument, which should be an
object containing any of these fields (only <code>ecmaVersion</code> is
required):

<ul>
<li>ecmaVersion: Indicates the ECMAScript version to parse. Can be a</li>
</ul>
 number, either in year (<code>2022</code>) or plain version number (<code>6</code>) form,
 or <code>"latest"</code> (the latest the library supports). This influences
 support for strict mode, the set of reserved words, and support for
 new syntax features.

NOTE: Only 'stage 4' (finalized) ECMAScript features are being
 implemented by Acorn. Other proposed new features must be
 implemented through plugins.

<ul>
<li>sourceType: Indicate the mode the code should be parsed in. Can be</li>
</ul>
 either <code>"script"</code>, <code>"module"</code> or <code>"commonjs"</code>. This influences global strict mode
 and parsing of <code>import</code> and <code>export</code> declarations.

NOTE: If set to <code>"module"</code>, then static <code>import</code> / <code>export</code> syntax
 will be valid, even if <code>ecmaVersion</code> is less than 6. If set to <code>"commonjs"</code>,
 it is the same as <code>"script"</code> except that the top-level scope behaves like a function.

<ul>
<li>onInsertedSemicolon: If given a callback, that callback will be</li>
</ul>
 called whenever a missing semicolon is inserted by the parser. The
 callback will be given the character offset of the point where the
 semicolon is inserted as argument, and if <code>locations</code> is on, also a
 <code>{line, column}</code> object representing this position.

<ul>
<li>onTrailingComma: Like <code>onInsertedSemicolon</code>, but for trailing</li>
</ul>
 commas.

<ul>
<li>allowReserved: If <code>false</code>, using a reserved word will generate</li>
</ul>
 an error. Defaults to <code>true</code> for <code>ecmaVersion</code> 3, <code>false</code> for higher
 versions. When given the value <code>"never"</code>, reserved words and
 keywords can also not be used as property names (as in Internet
 Explorer's old parser).

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各位师傅觉得这个方案怎么样？有更好的做法吗？