31 lines
777 B
JavaScript
31 lines
777 B
JavaScript
//#region src/function/once.ts
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/**
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* Creates a function that is restricted to invoking the provided function `func` once.
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* Repeated calls to the function will return the value from the first invocation.
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*
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* @template F - The type of function.
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* @param func - The function to restrict.
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* @returns A new function that invokes `func` once and caches the result.
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*
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* @example
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* const initialize = once(() => {
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* console.log('Initialized!');
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* return true;
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* });
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*
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* initialize(); // Logs: 'Initialized!' and returns true
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* initialize(); // Returns true without logging
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*/
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function once(func) {
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let called = false;
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let cache;
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return function(...args) {
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if (!called) {
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called = true;
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cache = func(...args);
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}
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return cache;
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};
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}
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//#endregion
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exports.once = once;
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