Fix #16: Add the email helper back to the repo to reduce backward compatibility issues.

Author: pocketarc

system/helpers/email_helper.php

@@ -0,0 +1,85 @@
+<?php
+/**
+ * CodeIgniter
+ *
+ * An open source application development framework for PHP
+ *
+ * This content is released under the MIT License (MIT)
+ *
+ * Copyright (c) 2019 - 2022, CodeIgniter Foundation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ * @package	CodeIgniter
+ * @author	EllisLab Dev Team
+ * @copyright	Copyright (c) 2008 - 2014, EllisLab, Inc. (https://ellislab.com/)
+ * @copyright	Copyright (c) 2014 - 2019, British Columbia Institute of Technology (https://bcit.ca/)
+ * @copyright	Copyright (c) 2019 - 2022, CodeIgniter Foundation (https://codeigniter.com/)
+ * @license	https://opensource.org/licenses/MIT	MIT License
+ * @link	https://codeigniter.com
+ * @since	Version 1.0.0
+ * @filesource
+ */
+defined('BASEPATH') OR exit('No direct script access allowed');
+
+/**
+ * CodeIgniter Email Helpers
+ *
+ * @package		CodeIgniter
+ * @subpackage	Helpers
+ * @category	Helpers
+ * @author		EllisLab Dev Team
+ * @link		https://codeigniter.com/userguide3/helpers/email_helper.html
+ */
+
+// ------------------------------------------------------------------------
+
+if ( ! function_exists('valid_email'))
+{
+	/**
+	 * Validate email address
+	 *
+	 * @deprecated	3.0.0	Use PHP's filter_var() instead
+	 * @param	string	$email
+	 * @return	bool
+	 */
+	function valid_email($email)
+	{
+		return (bool) filter_var($email, FILTER_VALIDATE_EMAIL);
+	}
+}
+
+// ------------------------------------------------------------------------
+
+if ( ! function_exists('send_email'))
+{
+	/**
+	 * Send an email
+	 *
+	 * @deprecated	3.0.0	Use PHP's mail() instead
+	 * @param	string	$recipient
+	 * @param	string	$subject
+	 * @param	string	$message
+	 * @return	bool
+	 */
+	function send_email($recipient, $subject, $message)
+	{
+		return mail($recipient, $subject, $message);
+	}
+}