YYY && ! ('a' | 'b' | ZZZ) | 'something else'

##</code><code>##

XXX: YYY ('a' | 'b' | ZZZ) <reject>
   | 'something' 'else'

YYY: 'some string'
ZZZ: 'ww' | 'xx' | 'yy' | 'zz'

##</code><code>##

NonTerminator: SourceCharacter but not LineTerminator

##</code><code>##

NonTerminator: SourceCharacter |
               SourceCharacter LineTerminator <reject>

##</code><code>##

NonTerminator: SourceCharacter LineTerminator <reject>