xml_func.py: Added _if and _eq. Added cast() to throw SyntaxException if can't cast and use it in conv_items(). _merge: Check types of input using conv_items(strings.ustr, items).
xml_func.py: Added _if and _eq. Added cast() to throw SyntaxException if can't cast and use it in conv_items(). _merge: Check types of input using conv_items(strings.ustr, items).