15 lines
365 B
TypeScript
15 lines
365 B
TypeScript
export function intersperse<A>(as: A[], separator: (index: number) => A): A[] {
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return as.flatMap((a, i) => (i ? [separator(i), a] : [a]))
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}
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export function count<T>(arr: readonly T[], pred: (x: T) => unknown): number {
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let n = 0
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for (const x of arr) n += +!!pred(x)
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return n
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}
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export function uniq<T>(xs: Iterable<T>): T[] {
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return [...new Set(xs)]
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}
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