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3a515b92
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cagy
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# babel-traverse
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> babel-traverse maintains the overall tree state, and is responsible for replacing, removing, and adding nodes.
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## Install
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```sh
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$ npm install --save babel-traverse
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```
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## Usage
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We can use it alongside Babylon to traverse and update nodes:
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```js
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import * as babylon from "babylon";
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import traverse from "babel-traverse";
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const code = `function square(n) {
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return n * n;
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}`;
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const ast = babylon.parse(code);
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traverse(ast, {
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enter(path) {
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if (path.isIdentifier({ name: "n" })) {
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path.node.name = "x";
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}
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}
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});
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```
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[:book: **Read the full docs here**](https://github.com/thejameskyle/babel-handbook/blob/master/translations/en/plugin-handbook.md#babel-traverse)
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