.config/coc/extensions/node_modules/coc-prettier/node_modules/core-js/modules/esnext.iterator.flat-map.js

   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 getIteratorMethod = require('../internals/get-iterator-method');
   7 var createIteratorProxy = require('../internals/iterator-create-proxy');
   8 var callWithSafeIterationClosing = require('../internals/call-with-safe-iteration-closing');
   9
  10 var IteratorProxy = createIteratorProxy(function (arg) {
  11   var iterator = this.iterator;
  12   var result, mapped, iteratorMethod, innerIterator;
  13
  14   while (true) {
  15     if (innerIterator = this.innerIterator) {
  16       result = anObject(this.innerNext.call(innerIterator));
  17       if (!result.done) return result.value;
  18       this.innerIterator = this.innerNext = null;
  19     }
  20
  21     result = anObject(this.next.call(iterator, arg));
  22
  23     if (this.done = !!result.done) return;
  24
  25     mapped = callWithSafeIterationClosing(iterator, this.mapper, result.value);
  26     iteratorMethod = getIteratorMethod(mapped);
  27
  28     if (iteratorMethod === undefined) {
  29       throw TypeError('.flatMap callback should return an iterable object');
  30     }
  31
  32     this.innerIterator = innerIterator = anObject(iteratorMethod.call(mapped));
  33     this.innerNext = aFunction(innerIterator.next);
  34   }
  35 });
  36
  37 $({ target: 'Iterator', proto: true, real: true }, {
  38   flatMap: function flatMap(mapper) {
  39     return new IteratorProxy({
  40       iterator: anObject(this),
  41       mapper: aFunction(mapper),
  42       innerIterator: null,
  43       innerNext: null
  44     });
  45   }
  46 });