--- /dev/null
+/** Used to stand-in for `undefined` hash values. */
+var HASH_UNDEFINED = '__lodash_hash_undefined__';
+
+/**
+ * Adds `value` to the array cache.
+ *
+ * @private
+ * @name add
+ * @memberOf SetCache
+ * @alias push
+ * @param {*} value The value to cache.
+ * @returns {Object} Returns the cache instance.
+ */
+function setCacheAdd(value) {
+ this.__data__.set(value, HASH_UNDEFINED);
+ return this;
+}
+
+module.exports = setCacheAdd;