Bump to v4.0.0.

internal/stackDelete.js

@@ -0,0 +1,20 @@
+define(['./assocDelete'], function(assocDelete) {
+
+  /**
+   * Removes `key` and its value from the stack.
+   *
+   * @private
+   * @name delete
+   * @memberOf Stack
+   * @param {string} key The key of the value to remove.
+   * @returns {boolean} Returns `true` if the entry was removed, else `false`.
+   */
+  function stackDelete(key) {
+    var data = this.__data__,
+        array = data.array;
+
+    return array ? assocDelete(array, key) : data.map['delete'](key);
+  }
+
+  return stackDelete;
+});