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node_modules/webpack/lib/util/MapHelpers.js

@@ -0,0 +1,22 @@
+/*
+	MIT License http://www.opensource.org/licenses/mit-license.php
+	Author Tobias Koppers @sokra
+*/
+
+"use strict";
+
+/**
+ * @template K
+ * @template V
+ * @param {Map<K, V>} map a map
+ * @param {K} key the key
+ * @param {function(): V} computer compute value
+ * @returns {V} value
+ */
+exports.provide = (map, key, computer) => {
+	const value = map.get(key);
+	if (value !== undefined) return value;
+	const newValue = computer();
+	map.set(key, newValue);
+	return newValue;
+};