Project: syntax-tree/esast-util-from-estree

Package: esast-util-from-estree@1.3.0

  1. Dependents: 0
  2. esast utility to transform from estree
  1. util 145
  2. utility 141
  3. tree 44
  4. ast 37
  5. javascript 26
  6. ecmascript 10
  7. estree 9
  8. transform 7
  9. esast 5
  10. esast-util 4
  11. recma 3


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esast utility to transform from estree.


What is this?

This package applies some transforms to a cloned, given estree to make it compatible with unist. It:

When should I use this?

The transform applied by this utility is often optional: estrees can be used in most places where esast can be used, and vice versa. But, if you come from a unist background and want to deal with JavaScript, or want to use unist utilities with JavaScript, this helps a lot.


This package is ESM only. In Node.js (version 16+), install with npm:

npm install esast-util-from-estree

In Deno with esm.sh:

import {fromEstree} from 'https://esm.sh/esast-util-from-estree@2'

In browsers with esm.sh:

<script type="module">
  import {fromEstree} from 'https://esm.sh/esast-util-from-estree@2?bundle'


import {parse} from 'acorn'
import {fromEstree} from './index.js'

// Make acorn support comments and positional info.
/** @type {Array<import('acorn').Comment>} */
const comments = []
/** @type {import('estree').Program} */
// @ts-expect-error: acorn looks like estree.
const estree = parse(
  'export function x() { /* Something senseless */ console.log(/(?:)/ + 1n) }',
    sourceType: 'module',
    ecmaVersion: 'latest',
    locations: true,
    onComment: comments
estree.comments = comments

const esast = fromEstree(estree)



  type: 'Program',
  body: [
      type: 'ExportNamedDeclaration',
      declaration: [Object],
      specifiers: [],
      source: null,
      position: [Object]
  sourceType: 'module',
  comments: [
      type: 'Block',
      value: ' Something senseless ',
      position: [Object]
  position: {
    start: {line: 1, column: 1, offset: 0},
    end: {line: 1, column: 75, offset: 74}


This package exports the identifier fromEstree. There is no default export.

fromEstree(estree[, options])

Turn an estree into an esast.


Clean clone of estree (UnistNode).


Configuration (TypeScript Type).



This package is fully typed with TypeScript. It exports the additional type Options.


Projects maintained by the unified collective are compatible with maintained versions of Node.js.

When we cut a new major release, we drop support for unmaintained versions of Node. This means we try to keep the current release line, esast-util-from-estree@^2, compatible with Node.js 16.


See contributing.md in syntax-tree/.github for ways to get started. See support.md for ways to get help.

This project has a code of conduct. By interacting with this repository, organization, or community you agree to abide by its terms.


MIT © Titus Wormer