38 lines
891 B
JavaScript
38 lines
891 B
JavaScript
/**
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* @param {Function[]} functions
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* @param {number} n
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* @return {Function}
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*/
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var promisePool = async function(functions, n) {
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return new Promise((resolve, reject) => {
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let in_progress = 0;
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let next = 0;
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function progress() {
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if (next >= functions.length) {
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if (in_progress == 0) {
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resolve();
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}
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return;
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}
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while (in_progress < n && next < functions.length) {
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in_progress++;
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functions[next++]().then(() => {
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in_progress--;
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progress();
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});
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}
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}
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progress();
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});
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};
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/**
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* const sleep = (t) => new Promise(res => setTimeout(res, t));
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* promisePool([() => sleep(500), () => sleep(400)], 1)
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* .then(console.log) // After 900ms
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*/
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