tree-crawl

tree-crawl

Generic tree traversal library.

tree-crawl is a lightweight tree crawler, well, technically walker. But the name was already taken you know...

It lets your easily walk any tree in pre-order or post-order. It supports in-place mutation of the tree including structural ones and does not 💥 when you move nodes around.

Install

npm install --save tree-crawl

Usage

import crawl from 'tree-crawl'

// traverse the tree in pre-order
crawl(tree, console.log)
crawl(tree, console.log, { order: 'pre' })

// traverse the tree in post-order
crawl(tree, console.log, { order: 'post' })

// traverse the tree using `childNodes` as the children key
crawl(tree, console.log, { childrenKey: 'childNodes' }

// skip a node and its children
crawl(tree, (node, context) => {
  if ('foo' === node.type) {
    context.skip()
  }
  console.log(node)
})

// break the walk
crawl(tree, (node, context) => {
  if ('foo' === node.type) {
    console.log(node)
    context.break()
  }
})

// remove a node
crawl(tree, (node, context) => {
  if ('foo' === node.type) {
    const parentChildren = node.parent.children
    parentChildren.splice(parentChildren.indexOf(node))
    context.remove()
  }
})

API

See the api documentation.

License

MIT © Nicolas Gryman