Initial Commit

inc/traits/trait-singleton.php

@@ -0,0 +1,67 @@
+<?php
+/**
+ * A trait to be included in entities to enable REST API endpoints.
+ *
+ * @package WP_Ultimo
+ * @subpackage Apis
+ * @since 2.0.0
+ */
+
+namespace WP_Ultimo\Traits;
+
+/**
+ * Singleton trait.
+ */
+trait Singleton {
+
+	/**
+	 * Makes sure we are only using one instance of the class
+	 *
+	 * @var object
+	 */
+	public static $instance;
+
+	/**
+	 * Returns the instance of WP_Ultimo
+	 *
+	 * @return object
+	 */
+	public static function get_instance() {
+
+		if (!static::$instance instanceof static) {
+
+			static::$instance = new static();
+
+			static::$instance->init();
+
+		} // end if;
+
+		return static::$instance;
+
+	} // end get_instance;
+
+	/**
+	 * Runs only once, at the first instantiation of the Singleton.
+	 *
+	 * @since 2.0.0
+	 * @return void
+	 */
+	public function init() {
+
+		$this->has_parents() && method_exists(get_parent_class($this), 'init') && parent::init();
+
+	} // end init;
+
+	/**
+	 * Check if the current class has parents.
+	 *
+	 * @since 2.0.11
+	 * @return boolean
+	 */
+	public function has_parents() {
+
+		return (bool) class_parents($this);
+
+	} // end has_parents;
+
+} // end trait Singleton;