27 lines
477 B
JavaScript
27 lines
477 B
JavaScript
'use strict';
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Object.defineProperty(exports, '__esModule', {
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value: true,
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});
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exports.groupBy = groupBy;
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/**
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* Groups array items into a Map, given a function to produce grouping key.
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*/
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function groupBy(list, keyFn) {
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const result = new Map();
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for (const item of list) {
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const key = keyFn(item);
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const group = result.get(key);
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if (group === undefined) {
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result.set(key, [item]);
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} else {
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group.push(item);
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}
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}
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return result;
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}
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