10 lines
230 B
TypeScript
10 lines
230 B
TypeScript
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interface Array<T> {
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flatJoinOn<E, J>(by: (item: T) => J): Array<E>;
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}
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Array.prototype.flatJoinOn = function (f: Function) {
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return this.groupBy(f).reduce((ys: any, x: any) => {
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return ys.concat(f.call(this, x));
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}, []);
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};
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