[type]
Parser

[grammar]
grammar T;
@parser::members {<InitBooleanMember("enumKeyword",True())>}
primary
    :   ID {<AppendStr("\"ID \"", "$ID.text"):writeln()>}
    |   {<GetMember("enumKeyword"):Not()>}? 'enum' {<writeln("\"enum\"")>}
    ;
ID : [a-z]+ ;
WS : [ \t\n\r]+ -> skip ;

[start]
primary

[input]
enum

[errors]
"""line 1:0 no viable alternative at input 'enum'
"""