      */
     public static func && (left: Where, right: Where?) -> Where {
         
-        if right != nil {
-            return left && right!
-        }
-        else {
-            
-            return left
-        }
+        if let right = right {
+            
+            return left && right
+        }
+        return left
     }
     
     /**

     */
    public static func && (left: Where?, right: Where) -> Where {
        
        if left != nil {
            return left && right
        }
        else {
            
            return right
        }
    }
    
    /**

     */
    public static func || (left: Where?, right: Where) -> Where {
        
        if let left = left {
            
            return left || right
        }
        return right
    }
    
    /**
