10 lines
245 B
TypeScript
10 lines
245 B
TypeScript
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export function groupBy<T, K extends keyof any>(arr: T[], key: (i: T) => K): Record<K, T[]> {
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return arr.reduce(
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(groups, item) => {
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(groups[key(item)] ||= []).push(item);
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return groups;
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},
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{} as Record<K, T[]>,
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);
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}
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