Paul Frazee
25 lines
571 B
TypeScript
25 lines
571 B
TypeScript
type BundledFn<Args extends readonly unknown[], Res> = (
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...args: Args
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) => Promise<Res>
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/**
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* A helper which ensures that multiple calls to an async function
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* only produces one in-flight request at a time.
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*/
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export function bundleAsync<Args extends readonly unknown[], Res>(
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fn: BundledFn<Args, Res>,
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): BundledFn<Args, Res> {
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let promise: Promise<Res> | undefined
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return async (...args) => {
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if (promise) {
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return promise
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}
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promise = fn(...args)
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try {
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return await promise
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} finally {
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promise = undefined
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}
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}
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}
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