[6a3a178] | 1 | 'use strict';
|
---|
| 2 | // https://github.com/tc39/proposal-iterator-helpers
|
---|
| 3 | var $ = require('../internals/export');
|
---|
| 4 | var aFunction = require('../internals/a-function');
|
---|
| 5 | var anObject = require('../internals/an-object');
|
---|
| 6 | var createAsyncIteratorProxy = require('../internals/async-iterator-create-proxy');
|
---|
| 7 | var getAsyncIteratorMethod = require('../internals/get-async-iterator-method');
|
---|
| 8 |
|
---|
| 9 | var AsyncIteratorProxy = createAsyncIteratorProxy(function (arg, Promise) {
|
---|
| 10 | var state = this;
|
---|
| 11 | var mapper = state.mapper;
|
---|
| 12 | var innerIterator, iteratorMethod;
|
---|
| 13 |
|
---|
| 14 | return new Promise(function (resolve, reject) {
|
---|
| 15 | var outerLoop = function () {
|
---|
| 16 | try {
|
---|
| 17 | Promise.resolve(anObject(state.next.call(state.iterator, arg))).then(function (step) {
|
---|
| 18 | try {
|
---|
| 19 | if (anObject(step).done) {
|
---|
| 20 | state.done = true;
|
---|
| 21 | resolve({ done: true, value: undefined });
|
---|
| 22 | } else {
|
---|
| 23 | Promise.resolve(mapper(step.value)).then(function (mapped) {
|
---|
| 24 | try {
|
---|
| 25 | iteratorMethod = getAsyncIteratorMethod(mapped);
|
---|
| 26 | if (iteratorMethod !== undefined) {
|
---|
| 27 | state.innerIterator = innerIterator = anObject(iteratorMethod.call(mapped));
|
---|
| 28 | state.innerNext = aFunction(innerIterator.next);
|
---|
| 29 | return innerLoop();
|
---|
| 30 | } reject(TypeError('.flatMap callback should return an iterable object'));
|
---|
| 31 | } catch (error2) { reject(error2); }
|
---|
| 32 | }, reject);
|
---|
| 33 | }
|
---|
| 34 | } catch (error1) { reject(error1); }
|
---|
| 35 | }, reject);
|
---|
| 36 | } catch (error) { reject(error); }
|
---|
| 37 | };
|
---|
| 38 |
|
---|
| 39 | var innerLoop = function () {
|
---|
| 40 | if (innerIterator = state.innerIterator) {
|
---|
| 41 | try {
|
---|
| 42 | Promise.resolve(anObject(state.innerNext.call(innerIterator))).then(function (result) {
|
---|
| 43 | try {
|
---|
| 44 | if (anObject(result).done) {
|
---|
| 45 | state.innerIterator = state.innerNext = null;
|
---|
| 46 | outerLoop();
|
---|
| 47 | } else resolve({ done: false, value: result.value });
|
---|
| 48 | } catch (error1) { reject(error1); }
|
---|
| 49 | }, reject);
|
---|
| 50 | } catch (error) { reject(error); }
|
---|
| 51 | } else outerLoop();
|
---|
| 52 | };
|
---|
| 53 |
|
---|
| 54 | innerLoop();
|
---|
| 55 | });
|
---|
| 56 | });
|
---|
| 57 |
|
---|
| 58 | $({ target: 'AsyncIterator', proto: true, real: true }, {
|
---|
| 59 | flatMap: function flatMap(mapper) {
|
---|
| 60 | return new AsyncIteratorProxy({
|
---|
| 61 | iterator: anObject(this),
|
---|
| 62 | mapper: aFunction(mapper),
|
---|
| 63 | innerIterator: null,
|
---|
| 64 | innerNext: null
|
---|
| 65 | });
|
---|
| 66 | }
|
---|
| 67 | });
|
---|