jiapengyu
44 lines
1.4 KiB
JavaScript
44 lines
1.4 KiB
JavaScript
import _arity from './internal/_arity';
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import _curry2 from './internal/_curry2';
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import _has from './internal/_has';
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/**
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* A customisable version of [`R.memoize`](#memoize). `memoizeWith` takes an
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* additional function that will be applied to a given argument set and used to
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* create the cache key under which the results of the function to be memoized
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* will be stored. Care must be taken when implementing key generation to avoid
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* clashes that may overwrite previous entries erroneously.
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*
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*
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* @func
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* @memberOf R
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* @since v0.24.0
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* @category Function
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* @sig (*... -> String) -> (*... -> a) -> (*... -> a)
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* @param {Function} fn The function to generate the cache key.
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* @param {Function} fn The function to memoize.
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* @return {Function} Memoized version of `fn`.
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* @see R.memoize
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* @example
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*
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* let count = 0;
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* const factorial = R.memoizeWith(R.identity, n => {
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* count += 1;
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* return R.product(R.range(1, n + 1));
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* });
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* factorial(5); //=> 120
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* factorial(5); //=> 120
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* factorial(5); //=> 120
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* count; //=> 1
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*/
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var memoizeWith = /*#__PURE__*/_curry2(function memoizeWith(mFn, fn) {
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var cache = {};
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return _arity(fn.length, function () {
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var key = mFn.apply(this, arguments);
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if (!_has(key, cache)) {
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cache[key] = fn.apply(this, arguments);
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}
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return cache[key];
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});
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});
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export default memoizeWith; |