[antlr-interest] NullPointerException in actions for recurring rules
Dariusz Dwornikowski
dariusz.dwornikowski at cs.put.poznan.pl
Sun Jun 26 06:03:59 PDT 2011
Hello Again,
What is the proper way to handle expression on abstract symbols (instead of
1+2+3+4, ive got only a+b+c etc)
rmdef returns [ProcessDef process]
: ^(PEPADEF pan=IDENT a=expression)
{
process = new ProcessDef();
process.setLHS($pan.text);
}
;
expression
: ^(COOP a=expression b=expression)
| ^(PREFIX a=expression b=expression) { print($a.text); }
| ^(CHOICE a=expression b=expression)
| procek=IDENT
;
In this case print($a.text); causes NullPointerException,
--
Pozdrawiam,
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Dariusz Dwornikowski,
Institute of Computing Science, Poznań University of Technology
www.cs.put.poznan.pl/ddwornikowski/
room 421 WE | tel. +48 61 665 21 24 | mobile: +48 533 890 600
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