61 lines
1.7 KiB
Plaintext
61 lines
1.7 KiB
Plaintext
'use strict';
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var $TypeError = require('es-errors/type');
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var Call = require('es-abstract/2024/Call');
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var GetIteratorDirect = require('../aos/GetIteratorDirect');
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var IsCallable = require('es-abstract/2024/IsCallable');
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var IteratorClose = require('es-abstract/2024/IteratorClose');
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var IteratorStepValue = require('es-abstract/2024/IteratorStepValue');
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var ThrowCompletion = require('es-abstract/2024/ThrowCompletion');
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var Type = require('es-abstract/2024/Type');
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module.exports = function reduce(reducer) {
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if (this instanceof reduce) {
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throw new $TypeError('`reduce` is not a constructor');
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}
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var O = this; // step 1
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if (Type(O) !== 'Object') {
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throw new $TypeError('`this` value must be an Object'); // step 2
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}
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if (!IsCallable(reducer)) {
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throw new $TypeError('`reducer` must be a function'); // step 3
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}
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var iterated = GetIteratorDirect(O); // step 4
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var accumulator;
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var counter;
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if (arguments.length < 2) { // step 6
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accumulator = IteratorStepValue(iterated); // step 6.a
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if (iterated['[[Done]]']) {
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throw new $TypeError('Reduce of empty iterator with no initial value');
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}
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counter = 1;
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} else { // step 7
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accumulator = arguments[1]; // step 7.a
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counter = 0;
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}
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// eslint-disable-next-line no-constant-condition
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while (true) { // step 8
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var value = IteratorStepValue(iterated); // step 8.a
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if (iterated['[[Done]]']) {
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return accumulator; // step 8.b
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}
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try {
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var result = Call(reducer, void undefined, [accumulator, value, counter]); // step 8.d
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accumulator = result; // step 8.f
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} catch (e) {
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// close iterator // step 8.e
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IteratorClose(
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iterated,
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ThrowCompletion(e)
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);
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}
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counter += 1; // step 8.g
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}
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};
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