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- import _arity from "./internal/_arity.js";
- import _curry2 from "./internal/_curry2.js";
- import _has from "./internal/_has.js";
- /**
- * Takes a string-returning function `keyGen` and a function `fn` and returns
- * a new function that returns cached results for subsequent
- * calls with the same arguments.
- *
- * When the function is invoked, `keyGen` is applied to the same arguments
- * and its result becomes the cache key. If the cache contains something
- * under that key, the function simply returns it and does not invoke `fn` at all.
- *
- * Otherwise `fn` is applied to the same arguments and its return value
- * is cached under that key and returned by the function.
- *
- * Care must be taken when implementing `keyGen` to avoid key collision,
- * or if tracking references, memory leaks and mutating arguments.
- *
- * @func
- * @memberOf R
- * @since v0.24.0
- * @category Function
- * @sig (*... -> String) -> (*... -> a) -> (*... -> a)
- * @param {Function} keyGen The function to generate the cache key.
- * @param {Function} fn The function to memoize.
- * @return {Function} Memoized version of `fn`.
- * @example
- * const withAge = memoizeWith(o => `${o.birth}/${o.death}`, ({birth, death}) => {
- * // ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ^^^^^^^^^^^^^^^^^^^^^
- * // keyGen fn
- * console.log(`computing age for ${birth}/${death}`);
- * return ({birth, death, age: death - birth});
- * });
- *
- * withAge({birth: 1921, death: 1999});
- * //=> LOG: computing age for 1921/1999
- * //=> {birth: 1921, death: 1999, age: 78} (returned from fn)
- *
- * withAge({birth: 1921, death: 1999});
- * //=> {birth: 1921, death: 1999, age: 78} (returned from cache)
- */
- var memoizeWith =
- /*#__PURE__*/
- _curry2(function memoizeWith(keyGen, fn) {
- var cache = {};
- return _arity(fn.length, function () {
- var key = keyGen.apply(this, arguments);
- if (!_has(key, cache)) {
- cache[key] = fn.apply(this, arguments);
- }
- return cache[key];
- });
- });
- export default memoizeWith;
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