Function Once Wrapper

easyJS SpecificJS / TS3 tests

Problem Statement

Implement a function `once(fn)` that ensures `fn` can only be called once. Subsequent invocations return the value returned by the first call, without executing `fn` again.

Examples

Example 1:
let counter = 0;
const init = once(() => ++counter);
init(); // 1
init(); // 1
console.log(counter); // 1

JavaScript & TypeScript starter code included

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Function Once Wrapper

Problem Statement

Examples

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