default namespace = "http://sample.com"
namespace foreign = "http://oliver.com"
# start enumerates all possible root elements
start = example | sample | \empty
## The example element must be empty
example = element example { empty }
## The empty element must be empty
# note use of a keyword as an identifier
\empty = element empty { empty }
# note use of character escape \x{61} for letter 'a'
s\x{61}mple =
	## The sample element is for Goldilocks
  element sample {
		[ foreign:more="yes" ]
		attribute porridge { "hot" | "cold" | "perfect" },
		\x{61}ttribute bed { "hard" | "soft" | "perfect" }
	}
