| 1 | 'use strict';
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| 2 |
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| 3 | var $ = require('../internals/export');
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| 4 | var iterate = require('../internals/iterate');
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| 5 | var aFunction = require('../internals/a-function');
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| 6 | var anObject = require('../internals/an-object');
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| 7 |
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| 8 | $({ target: 'Iterator', proto: true, real: true }, {
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| 9 | reduce: function reduce(reducer /* , initialValue */) {
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| 10 | anObject(this);
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| 11 | aFunction(reducer);
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| 12 | var noInitial = arguments.length < 2;
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| 13 | var accumulator = noInitial ? undefined : arguments[1];
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| 14 | iterate(this, function (value) {
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| 15 | if (noInitial) {
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| 16 | noInitial = false;
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| 17 | accumulator = value;
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| 18 | } else {
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| 19 | accumulator = reducer(accumulator, value);
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| 20 | }
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| 21 | }, undefined, false, true);
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| 22 | if (noInitial) throw TypeError('Reduce of empty iterator with no initial value');
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| 23 | return accumulator;
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| 24 | }
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| 25 | });
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