| 12345678910111213141516171819202122232425262728293031 | 
							- 'use strict';
 
- // https://tc39.github.io/proposal-setmap-offrom/
 
- var bind = require('../internals/function-bind-context');
 
- var call = require('../internals/function-call');
 
- var aCallable = require('../internals/a-callable');
 
- var aConstructor = require('../internals/a-constructor');
 
- var isNullOrUndefined = require('../internals/is-null-or-undefined');
 
- var iterate = require('../internals/iterate');
 
- var push = [].push;
 
- module.exports = function from(source /* , mapFn, thisArg */) {
 
-   var length = arguments.length;
 
-   var mapFn = length > 1 ? arguments[1] : undefined;
 
-   var mapping, array, n, boundFunction;
 
-   aConstructor(this);
 
-   mapping = mapFn !== undefined;
 
-   if (mapping) aCallable(mapFn);
 
-   if (isNullOrUndefined(source)) return new this();
 
-   array = [];
 
-   if (mapping) {
 
-     n = 0;
 
-     boundFunction = bind(mapFn, length > 2 ? arguments[2] : undefined);
 
-     iterate(source, function (nextItem) {
 
-       call(push, array, boundFunction(nextItem, n++));
 
-     });
 
-   } else {
 
-     iterate(source, push, { that: array });
 
-   }
 
-   return new this(array);
 
- };
 
 
  |