u/leftpadesque/memoize.ts


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import type { Callable } from '@emprespresso/pengueno';

export const memoize = <R, F extends Callable<R>>(fn: F): F => {
    const cache = new Map<string, R>();
    return ((...args: unknown[]): R => {
        const key = JSON.stringify(args);
        if (cache.has(key)) {
            return cache.get(key)!;
        }
        const res = fn.apply(args);
        cache.set(key, res);
        return res;
    }) as F;
};