up n_m

node_modules/webpack/lib/util/memoize.js

@@ -0,0 +1,34 @@
+/*
+	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
+			// eslint-disable-next-line no-warning-comments
+			// @ts-ignore
+			fn = undefined;
+			return /** @type {T} */ (result);
+		}
+	};
+};
+
+module.exports = memoize;