45 lines
1.0 KiB
JavaScript
45 lines
1.0 KiB
JavaScript
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"use strict";
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Object.defineProperty(exports, "__esModule", { value: true });
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exports.createRace = void 0;
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/**
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* Constructs a function that will only invoke the first function passed to it
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* concurrently. Once the function has been executed, the racer will be reset
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* and the next invocation will be allowed to execute.
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*
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* Example:
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*
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* ```ts
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* import {createRace} from 'thingies/es2020/createRace';
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*
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* const race = createRace();
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*
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* race(() => {
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* race(() => {
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* console.log('This will not be executed');
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* });
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* console.log('This will be executed');
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* });
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*
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* race(() => {
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* console.log('This will be executed');
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* });
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* ```
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*
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* @returns A "race" function that will only invoke the first function passed to it.
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*/
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const createRace = () => {
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let invoked = false;
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return (fn) => {
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if (invoked)
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return;
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invoked = true;
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try {
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return fn();
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}
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finally {
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invoked = false;
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}
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};
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};
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exports.createRace = createRace;
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