Question

I have the following production in my ANTLR grammar:

rich_newick_string 
:    str=(.*';') { stack.pushRichNewickString($str.text); };

I expected some string match to be passed to my pushRichNewickString method, but instead I’m getting null. What am I doing wrong?

Thanks.

Answer 1

You can’t put more than one lexer/parser rule inside parenthesis and then assign a label to it:

rule
  :   label=(ruleA ruleB ruleC) { /* use $label.text in here */ }
  ;

Try this instead:

rule
  :   label=tempRule { /* use $label.text in here */ }
  ;

tempRule
  :  ruleA ruleB ruleC
  ;

Also, do you really have a .* inside your parser rule? Are you aware this does not match zero or more characters, but zero or more tokens instead?