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