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 class GameObject {
    get root() {
        // get topmost game object, the "world"
        let obj = this;
        while (obj.parent != null) {
            obj = obj.parent;
        }
        return obj;
    }
    sendMsg(str, data) {
        // relay a message directly to the world, to be passed down
        this.root.receiveMsg(this, str, data);
    }
}

class Tree {
  constructor(val) {
    let temp = Object.assign(this, val);
    if( typeof temp !== 'object') {
      throw TypeError('Tree expects an object');
    } else {
      Object.keys(temp).forEach((key, index) => {
        if(typeof temp[key] === 'object') {
          temp[key] = Tree.convert(temp[key])
        } else {
          temp[key] = Object.setPrototypeOf(new temp[key].constructor(temp[key]), Leaf.prototype);
        }
        temp[key].parent = (temp.__proto__ == Tree.prototype) ? temp : Object.setPrototypeOf(temp, Tree.prototype);

class Tree {
  constructor(initialContents) {
    this.nodes = [];
    if (!!initialContents) {
      this.nodes.concat(initialContents)
    }
  }

  add(item) {
    this.nodes.push(item);
  }
}

class Tree {
  constructor(val) {
    let temp = Object.assign({}, val);
    if( typeof temp !== 'object') {
      throw TypeError('Tree expects an object');
    } else {
      Object.keys(temp).forEach((key, index) => {
        if(typeof temp[key] === 'object') {
          temp[key] = Tree.convert(temp[key])
        } else {
          temp[key] = new Branch(key)
        }
        temp[key].parent = temp
      })
    }
    this.__val__ = temp
  }
  static convert( obj ) {
    obj = new Branch(obj);

  function j(a,b,c) { return `${a}+${b}+${c}` };
  j = Function.reArg(j, [2, 1, 0])
  j(1,2,3);             // '3+2+1'

  XtraUtils.Function.addMethod('reArg', (function(){
    const _toString = Object.prototype.toString,
      _isNumber = val => typeof val === 'number',
      _reOrg=(a,c)=>{let b=Array(a.length).fill();a.forEach((a,d)=>{b[c[d]]=a;});return b;},
      _regularize=(a)=>{let b=[];if('[object Array]'===_toString.call(a)){return a;}keys(a).filter(_isNumber).forEach((c)=>{b[c]=a[c];});return b;};
    /**
     * Re-arranges the arguments to a function.
     * @param {Function} fn The function to remap the arguments.

let arr = []
if( true ) {
  const val = Symbol('__val__')
  class Tree {
    constructor(value) {
      let temp = Object.assign({}, value);
      if( typeof temp !== 'object') {
        throw TypeError('Tree expects an object');
      } else {
        Object.keys(temp).forEach((key, index) => {
          if(typeof temp[key] === 'object') {
            temp[key] = Tree.convert(temp[key])
          } else {
            temp[key] = new Branch(key)
          }
          temp[key].parent = temp
        })