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-rw-r--r--node_modules/webpack/lib/util/memoize.js32
1 files changed, 32 insertions, 0 deletions
diff --git a/node_modules/webpack/lib/util/memoize.js b/node_modules/webpack/lib/util/memoize.js
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+++ b/node_modules/webpack/lib/util/memoize.js
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+/*
+ MIT License http://www.opensource.org/licenses/mit-license.php
+*/
+
+"use strict";
+
+/** @template T @typedef {function(): T} FunctionReturning */
+
+/**
+ * @template T
+ * @param {FunctionReturning<T>} fn memorized function
+ * @returns {FunctionReturning<T>} new function
+ */
+const memoize = fn => {
+ let cache = false;
+ /** @type {T | undefined} */
+ let result = undefined;
+ return () => {
+ if (cache) {
+ return /** @type {T} */ (result);
+ } else {
+ result = fn();
+ cache = true;
+ // Allow to clean up memory for fn
+ // and all dependent resources
+ fn = undefined;
+ return /** @type {T} */ (result);
+ }
+ };
+};
+
+module.exports = memoize;