Helper function used in memoization of an HTML Node.

memoizeNode.js

const elType = 'div'

module.exports = function memoizeNode (node) {
  var placeholder = null
  var element = null
  var args = null

  return function render () {
    const _args = arguments
    if (!element) {
      args = _args
      element = node
      return element
    } else {
      const isEqual = compare(args, _args)
      if (isEqual) {
        placeholder = document.createElement(elType) // <template> has no IE support :O
        placeholder.isSameNode = function (el) {
          el.isSameNode(element)
        }
        return placeholder
      } else {
        args = _args
        element = node
        return element
      }
    }
  }
}

// Compare two argument arrays
// ([any], [any]) -> bool
function compare (oldArgs, newArgs) {
  var ln = newArgs.length
  for (i = 0; i < ln; i++) {
    if (newArgs[i] !== oldArgs[i]) {
      return false
    }
  }
  return true
}