34 lines
967 B
JavaScript
34 lines
967 B
JavaScript
import { identity } from '../../function/identity.mjs';
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import { range } from '../../math/range.mjs';
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import { isArrayLike } from '../predicate/isArrayLike.mjs';
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function reduce(collection, iteratee = identity, accumulator) {
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if (!collection) {
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return accumulator;
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}
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let keys;
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let startIndex = 0;
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if (isArrayLike(collection)) {
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keys = range(0, collection.length);
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if (accumulator == null && collection.length > 0) {
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accumulator = collection[0];
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startIndex += 1;
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}
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}
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else {
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keys = Object.keys(collection);
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if (accumulator == null) {
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accumulator = collection[keys[0]];
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startIndex += 1;
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}
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}
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for (let i = startIndex; i < keys.length; i++) {
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const key = keys[i];
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const value = collection[key];
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accumulator = iteratee(accumulator, value, key, collection);
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}
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return accumulator;
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}
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export { reduce };
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