git.r.bdr.sh - rbdr/dotfiles/blob

   1 'use strict';
   2
   3 var setPrototypeOf = require('es5-ext/object/set-prototype-of')
   4   , d              = require('d')
   5   , Iterator       = require('../')
   6   , validIterable  = require('../valid-iterable')
   7
   8   , push = Array.prototype.push
   9   , defineProperties = Object.defineProperties
  10   , IteratorChain;
  11
  12 IteratorChain = function (iterators) {
  13         defineProperties(this, {
  14                 __iterators__: d('', iterators),
  15                 __current__: d('w', iterators.shift())
  16         });
  17 };
  18 if (setPrototypeOf) setPrototypeOf(IteratorChain, Iterator);
  19
  20 IteratorChain.prototype = Object.create(Iterator.prototype, {
  21         constructor: d(IteratorChain),
  22         next: d(function () {
  23                 var result;
  24                 if (!this.__current__) return { done: true, value: undefined };
  25                 result = this.__current__.next();
  26                 while (result.done) {
  27                         this.__current__ = this.__iterators__.shift();
  28                         if (!this.__current__) return { done: true, value: undefined };
  29                         result = this.__current__.next();
  30                 }
  31                 return result;
  32         })
  33 });
  34
  35 module.exports = function () {
  36         var iterators = [this];
  37         push.apply(iterators, arguments);
  38         iterators.forEach(validIterable);
  39         return new IteratorChain(iterators);
  40 };