default namespace = "http://hsivonen.iki.fi/FooML"
datatypes i = "http://hsivonen.iki.fi/datatype/permissive-id"

	start = foo.elem
	
	foo.elem = 
		element foo { foo.inner & foo.attrs }
	foo.attrs =
		(	foo.attrs.id?
		&	foo.attrs.idref?
		&	foo.attrs.idrefs?
		)
	foo.attrs.id =
		attribute id {
			i:ID
		}
	foo.attrs.idref =
		attribute idref {
			i:IDREF
		}
	foo.attrs.idrefs =
		attribute idrefs {
			i:IDREFS
		}
	foo.inner =
		( foo.elem* )
