Switched the Iterator implementation to a dedicated helper class (to hide the specific implementation, since it's pretty messy and may change).

src/iterpriv.cpp

@@ -0,0 +1,17 @@
+#include "crt.h"
+#include "iterpriv.h"
+
+namespace YAML
+{
+	IterPriv::IterPriv(): type(IT_NONE)
+	{
+	}
+
+	IterPriv::IterPriv(std::vector <Node *>::const_iterator it): seqIter(it), type(IT_SEQ)
+	{
+	}
+
+	IterPriv::IterPriv(std::map <Node *, Node *, ltnode>::const_iterator it): mapIter(it), type(IT_MAP)
+	{
+	}
+}