62 lines
1.2 KiB
Markdown
62 lines
1.2 KiB
Markdown
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# is-reference
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Utility for determining whether an AST node is a reference.
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`foo` is a reference in these cases:
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```js
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console.log(foo);
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var foo;
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function foo() {}
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function bar(foo) {}
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export { foo as x };
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```
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`foo` is *not* a reference in these cases:
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```js
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var obj = { foo: 1 };
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console.log(obj.foo);
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export { x as foo };
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```
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In all cases, `foo` is an `Identifier` node, but the two kinds must be treated differently for the purposes of scope analysis etc. (The examples are non-exhaustive.)
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## Installation
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```bash
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npm install is-reference
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```
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## Usage
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Example using [Acorn](https://github.com/ternjs/acorn) and [estree-walker](https://github.com/Rich-Harris/estree-walker):
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```js
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import { parse } from 'acorn';
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import { walk } from 'estree-walker';
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import is_reference from 'is-reference';
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const identifiers = [];
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const references = [];
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const ast = parse(`var a = b.c;`);
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walk(ast, {
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enter(node, parent) {
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if (node.type === 'Identifier') identifiers.push(node);
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if (is_reference(node, parent)) references.push(node);
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}
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});
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identifiers.forEach(node => console.log(node.name)); // a, b, c
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references.forEach(node => console.log(node.name)); // a, b
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```
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## License
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MIT
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