| 'use strict'; |
| // https://github.com/tc39/proposal-iterator-helpers |
| var $ = require('../internals/export'); |
| var aFunction = require('../internals/a-function'); |
| var anObject = require('../internals/an-object'); |
| var createIteratorProxy = require('../internals/create-iterator-proxy'); |
| var callWithSafeIterationClosing = require('../internals/call-with-safe-iteration-closing'); |
| |
| var IteratorProxy = createIteratorProxy(function (arg) { |
| var iterator = this.iterator; |
| var result = anObject(this.next.call(iterator, arg)); |
| var done = this.done = !!result.done; |
| if (!done) return callWithSafeIterationClosing(iterator, this.mapper, result.value); |
| }); |
| |
| $({ target: 'Iterator', proto: true, real: true }, { |
| map: function map(mapper) { |
| return new IteratorProxy({ |
| iterator: anObject(this), |
| mapper: aFunction(mapper) |
| }); |
| } |
| }); |