root: *(ws assignment ws).
assignment: identifier ws ":" ws +term ?block "." .
identifier : +'-ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890'.
ws : *' \t\r\n'.
block: ?("{\n" >"\n}" "\n}" ws).
term : factor ?"!" ws.
factor: ?'*+?' [identifier string chars until seq any].
string: '"' >'"' '"'.
chars : "'" >"'" "'".
until:">"[string chars].
seq: "(" ws +term ")".
any: "[" ws +term "]".