15 lines
293 B
Plaintext
15 lines
293 B
Plaintext
// @flow
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export default function uniqueBy<T>(arr: Array<T>, fn: T => any): Array<T> {
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const identifiers = new Set();
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return arr.filter(item => {
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const identifier = fn(item);
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if (!identifiers.has(identifier)) {
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identifiers.add(identifier);
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return true;
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}
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});
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}
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