up n_m

node_modules/algoliasearch-helper/src/DerivedHelper/index.js

@@ -0,0 +1,41 @@
+'use strict';
+
+var EventEmitter = require('@algolia/events');
+
+var inherits = require('../functions/inherits');
+
+/**
+ * A DerivedHelper is a way to create sub requests to
+ * Algolia from a main helper.
+ * @class
+ * @classdesc The DerivedHelper provides an event based interface for search callbacks:
+ *  - search: when a search is triggered using the `search()` method.
+ *  - result: when the response is retrieved from Algolia and is processed.
+ *    This event contains a {@link SearchResults} object and the
+ *    {@link SearchParameters} corresponding to this answer.
+ * @param {AlgoliaSearchHelper} mainHelper the main helper
+ * @param {function} fn the function to create the derived state
+ */
+function DerivedHelper(mainHelper, fn) {
+  this.main = mainHelper;
+  this.fn = fn;
+  this.lastResults = null;
+}
+
+inherits(DerivedHelper, EventEmitter);
+
+/**
+ * Detach this helper from the main helper
+ * @return {undefined}
+ * @throws Error if the derived helper is already detached
+ */
+DerivedHelper.prototype.detach = function () {
+  this.removeAllListeners();
+  this.main.detachDerivedHelper(this);
+};
+
+DerivedHelper.prototype.getModifiedState = function (parameters) {
+  return this.fn(parameters);
+};
+
+module.exports = DerivedHelper;