25 lines
945 B
JavaScript
25 lines
945 B
JavaScript
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'use strict';
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var call = require('../internals/function-call');
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var aCallable = require('../internals/a-callable');
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var anObject = require('../internals/an-object');
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var getIteratorDirect = require('../internals/get-iterator-direct');
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var createIteratorProxy = require('../internals/iterator-create-proxy');
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var callWithSafeIterationClosing = require('../internals/call-with-safe-iteration-closing');
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var IteratorProxy = createIteratorProxy(function () {
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var iterator = this.iterator;
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var result = anObject(call(this.next, iterator));
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var done = this.done = !!result.done;
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if (!done) return callWithSafeIterationClosing(iterator, this.mapper, [result.value, this.counter++], true);
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});
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// `Iterator.prototype.map` method
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// https://github.com/tc39/proposal-iterator-helpers
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module.exports = function map(mapper) {
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anObject(this);
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aCallable(mapper);
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return new IteratorProxy(getIteratorDirect(this), {
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mapper: mapper
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});
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};
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