feat: add ability to select nodes using alternate node models to simplify feed parsing and fallbacks

Author: Harrison Ifeanyichukwu

src/XPath.php

@@ -64,6 +64,38 @@ public function selectNodes(string $expression, DOMNode $context_node = null)
         return $result;
     }
 
+    /**
+     * queries the document and returns a single result item or null
+     *
+     *@return DOMNode|null
+    */
+    public function selectAltNode(string $expressions, DOMNode $context_node = null)
+    {
+        foreach(preg_split('/\s*\|\|\s*/', $expressions) as $expression) {
+            $result = $this->selectNode($expression, $context_node);
+            if ($result)
+                return $result;
+        }
+
+        return null;
+    }
+
+    /**
+     * queries the document and returns a DOMNodeList or null
+     *
+     *@return DOMNodeList|null
+    */
+    public function selectAltNodes(string $expressions, DOMNode $context_node = null)
+    {
+        foreach(preg_split('/\s*\|\|\s*/', $expressions) as $expression) {
+            $result = $this->selectNodes($expression, $context_node);
+            if ($result && $result->length > 0)
+                return $result;
+        }
+
+        return null;
+    }
+
     /**
      * returns the dom xpath
      *