esnext.async-iterator.take.js 739 B

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  1. 'use strict';
  2. // https://github.com/tc39/proposal-iterator-helpers
  3. var $ = require('../internals/export');
  4. var anObject = require('../internals/an-object');
  5. var toPositiveInteger = require('../internals/to-positive-integer');
  6. var createAsyncIteratorProxy = require('../internals/async-iterator-create-proxy');
  7. var AsyncIteratorProxy = createAsyncIteratorProxy(function (arg) {
  8. if (!this.remaining--) {
  9. this.done = true;
  10. return { done: true, value: undefined };
  11. } return this.next.call(this.iterator, arg);
  12. });
  13. $({ target: 'AsyncIterator', proto: true, real: true }, {
  14. take: function take(limit) {
  15. return new AsyncIteratorProxy({
  16. iterator: anObject(this),
  17. remaining: toPositiveInteger(limit)
  18. });
  19. }
  20. });