estraverse

Traversing an AST

This feature allows you to traverse an AST, visiting all nodes in a depth-first order. You can perform actions when entering or leaving each node.

const estraverse = require('estraverse');
const ast = { /* some AST object */ };
estraverse.traverse(ast, {
  enter: function (node) {
    console.log('Entering node:', node.type);
  },
  leave: function (node) {
    console.log('Leaving node:', node.type);
  }
});

Updating an AST

This feature allows you to update nodes in an AST during traversal. In this example, it renames identifiers from 'oldName' to 'newName'.

const estraverse = require('estraverse');
const ast = { /* some AST object */ };
estraverse.replace(ast, {
  enter: function (node) {
    if (node.type === 'Identifier' && node.name === 'oldName') {
      node.name = 'newName';
      return node;
    }
  }
});