ast-monkey-traverse/README.md

Utility library to traverse AST

<h1 align="center">ast-monkey-traverse</h1>

<p align="center">Utility library to traverse AST</p>

<p align="center">
  <a href="https://codsen.com/os/ast-monkey-traverse" rel="nofollow noreferrer noopener">
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## Install

This package is [pure ESM](https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c). If you're not ready yet, install an older version of this program, 2.1.0 (`npm i ast-monkey-traverse@2.1.0`).

```bash
npm i ast-monkey-traverse
```

## Quick Take

```js
import { strict as assert } from "assert";

import { traverse } from "ast-monkey-traverse";

const paths = [];
const source = {
  a: {
    foo: {
      bar: [
        {
          foo: "c",
        },
      ],
      d: {
        e: {
          foo: "f",
        },
      },
    },
  },
};

traverse(source, (key, val, innerObj) => {
  // if currently an object is traversed, you get both "key" and "val"
  // if it's array, only "key" is present, "val" is undefined
  let current = val !== undefined ? val : key;
  if (
    // it's object (not array)
    val !== undefined &&
    // and has the key we need
    key === "foo"
  ) {
    // push the path to array in the outer scope
    paths.push(innerObj.path);
  }
  return current;
});

// notice object-path notation "a.foo.bar.0.foo" - array segments use dots too:
assert.deepEqual(paths, ["a.foo", "a.foo.bar.0.foo", "a.foo.d.e.foo"]);
```

## Documentation

Please [visit codsen.com](https://codsen.com/os/ast-monkey-traverse/) for a full description of the API.

## Contributing

To report bugs or request features or assistance, [raise an issue](https://github.com/codsen/codsen/issues/new/choose) on GitHub.

## Licence

MIT License.

Copyright © 2010-2025 Roy Revelt and other contributors.

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