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unist-util-map

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unist utility to create a new tree by mapping all nodes with the given function.

Install

npm:

npm install unist-util-map

Usage

var u = require('unist-builder')
var map = require('unist-util-map')

var tree = u('tree', [
  u('leaf', 'leaf 1'),
  u('node', [u('leaf', 'leaf 2')]),
  u('void'),
  u('leaf', 'leaf 3')
])

var next = map(tree, function(node) {
  return node.type === 'leaf'
    ? Object.assign({}, node, {value: 'CHANGED'})
    : node
})

console.dir(next, {depth: null})

Yields:

{
  type: 'tree',
  children: [
    { type: 'leaf', value: 'CHANGED' },
    { type: 'node', children: [ { type: 'leaf', value: 'CHANGED' } ] },
    { type: 'void' },
    { type: 'leaf', value: 'CHANGED' }
  ]
}

…note that tree is not mutated.

API

map(tree, mapFn)

Create a new tree by mapping all nodes with the given function.

Parameters
  • tree (Node) — Tree to map
  • callback (Function) — Function that returns a new node
Returns

Node — New mapped tree.

function mapFn(node[, index, parent])

Function called with a node to produce a new node.

Parameters
  • node (Node) — Current node being processed
  • index (number?) — Index of node, or null
  • parent (Node?) — Parent of node, or null
Returns

Node — Node to be used in the new tree. Its children are not used: if the original node has children, those are mapped.

Related

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, organisation, or community you agree to abide by its terms.

License

MIT © azu