-simple ::= term | set.
-term ::= <word> | '"' <term> .. '"'.
-set ::= '@set' <setname>.
-attr ::= '@attr' <number> '=' <number>.
+simple ::= term | set.
+term ::= <word> | '"' <term> ... '"'.
+set ::= '@set' <setname>.
+attr ::= '@attr' <number> '=' <number>.