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    esast-util-from-estree
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    1.3.1 • Public • Published

    esast-util-from-estree

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    esast utility to transform from estree.

    Contents

    What is this?

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

    • makes sure nodes are plain JSON
    • adds unist positions
    • normalizes .bigint
    • remove attributes, selfClosing from JSXOpeningFragment
    • removes certain discouraged fields

    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.

    Install

    This package is ESM only. In Node.js (version 14.14+ and 16.0+), install with npm:

    npm install esast-util-from-estree

    In Deno with esm.sh:

    import {fromEstree} from 'https://esm.sh/esast-util-from-estree@1'

    In browsers with esm.sh:

    <script type="module">
      import {fromEstree} from 'https://esm.sh/esast-util-from-estree@1?bundle'
    </script>

    Use

    import {parse} from 'acorn'
    import {fromEstree} from 'esast-util-from-estree'
    
    // Make acorn support comments and positional info.
    const comments = []
    const esast = parse(
      'export function x() { /* Something senseless */ console.log(/(?:)/ + 1n) }',
      {sourceType: 'module', locations: true, onComment: comments}
    )
    esast.comments = comments
    
    console.log(fromEstree(esast))

    Yields:

    {
      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}
      }
    }

    API

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

    fromEstree(estree[, options])

    Turn an estree into an esast.

    Parameters
    Returns

    esast (UnistNode).

    Options

    Configuration (TypeScript Type).

    Fields
    • dirty (boolean, default: false) — leave discouraged fields in the tree

    Types

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

    Compatibility

    Projects maintained by the unified collective are compatible with all maintained versions of Node.js. As of now, that is Node.js 14.14+ and 16.0+. Our projects sometimes work with older versions, but this is not guaranteed.

    Contribute

    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.

    License

    MIT © Titus Wormer

    Install

    npm i esast-util-from-estree

    DownloadsWeekly Downloads

    164

    Version

    1.3.1

    License

    MIT

    Unpacked Size

    12.4 kB

    Total Files

    7

    Last publish

    Collaborators

    • wooorm
    • kmck