1 files changed, 76 insertions, 0 deletions
diff --git a/www/wiki/extensions/SemanticMediaWiki/src/Iterators/MappingIterator.php b/www/wiki/extensions/SemanticMediaWiki/src/Iterators/MappingIterator.php
new file mode 100644
index 00000000..0aa39888
--- /dev/null
+++ b/www/wiki/extensions/SemanticMediaWiki/src/Iterators/MappingIterator.php
@@ -0,0 +1,76 @@
+<?php
+
+namespace SMW\Iterators;
+
+use ArrayIterator;
+use Countable;
+use Iterator;
+use IteratorIterator;
+use RuntimeException;
+
+/**
+ * This iterator is expected to be called in combination with another iterator
+ * (or traversable/array) in order to apply a mapping on the returned current element
+ * during an iterative (foreach etc.) process.
+ *
+ * @license GNU GPL v2+
+ * @since 2.5
+ *
+ * @author mwjames
+ */
+class MappingIterator extends IteratorIterator implements Countable {
+
+	/**
+	 * @var callable
+	 */
+	private $callback;
+
+	/**
+	 * @var integer
+	 */
+	private $count = 1;
+
+	/**
+	 * @since 2.5
+	 *
+	 * @param Iterator|array $iterable
+	 * @param callable  $callback
+	 */
+	public function __construct( $iterable, callable $callback ) {
+
+		if ( is_array( $iterable ) ) {
+			$iterable = new ArrayIterator( $iterable );
+		}
+
+		if ( !$iterable instanceof Iterator ) {
+			throw new RuntimeException( "MappingIterator expected an Iterator" );
+		}
+
+		if ( $iterable instanceof Countable ) {
+			$this->count = $iterable->count();
+		}
+
+		parent::__construct( $iterable );
+		$this->callback = $callback;
+	}
+
+	/**
+	 * @see Countable::count
+	 * @since 2.5
+	 *
+	 * {@inheritDoc}
+	 */
+	public function count() {
+		return $this->count;
+	}
+
+	/**
+	 * @since 2.5
+	 *
+	 * {@inheritDoc}
+	 */
+	public function current() {
+		return call_user_func( $this->callback, parent::current() );
+	}
+
+}