Move Set::hasLoop() to new Algorithm\Loop

Author: clue

src/Loop.php

@@ -0,0 +1,35 @@
+<?php
+
+namespace Fhaculty\Graph\Algorithm;
+
+use Fhaculty\Graph\Algorithm\BaseSet;
+use Fhaculty\Graph\Edge\Base as Edge;
+use Fhaculty\Graph\Vertex;
+
+/**
+ * Basic algorithms for working with loop edges
+ *
+ * A loop (also called a self-loop or a "buckle") is an edge that connects a
+ * Vertex to itself. A simple graph contains no loops.
+ *
+ * @link http://en.wikipedia.org/wiki/Loop_%28graph_theory%29
+ */
+class Loop extends BaseSet
+{
+    /**
+     * checks whether this graph has any loops (edges from vertex to itself)
+     *
+     * @return boolean
+     * @uses Edge::isLoop()
+     */
+    public function hasLoop()
+    {
+        foreach ($this->set->getEdges() as $edge) {
+            if ($edge->isLoop()) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}