babel-traverse maintains the overall tree state, and is responsible for replacing, removing, and adding nodes.
sh
$ npm install --save babel-traverse
We can use it alongside Babylon to traverse and update nodes:
```js import * as babylon from "babylon"; import traverse from "babel-traverse";
const code = function square(n) {
return n * n;
}
;
const ast = babylon.parse(code);
traverse(ast, { enter(path) { if (path.isIdentifier({ name: "n" })) { path.node.name = "x"; } } }); ``` :book: Read the full docs here