--- /dev/null
+#define Val_ptr(p) ((value) (p))
+#define Val_option(p,f) ((p != NULL) ? ml_some(f(p)) : Val_unit)
+#define Val_mDOMString(s) (copy_string((char*) (s)))
+#define mDOMString_val(v) ((mDOMStringRef) String_val(v))
+#define mDOMNode_val(v) ((mDOMNodeRef) v)