[antlr-interest] [C target] mismatchRecover()

[Justin Murray]

Hello,

 

I am trying to turn off single token insertion and deletion error
recovery in my parser (C target). I found the following comment in
antlr3baserecognizer.c above the match() function.

 

/// Match current input symbol against ttype.  Upon error, do one token

/// insertion or deletion if possible.  

/// To turn off single token insertion or deletion error

/// recovery, override mismatchRecover() and have it call

/// plain mismatch(), which does not recover.  Then any error

/// in a rule will cause an exception and immediate exit from

/// rule.  Rule would recover by resynchronizing to the set of

/// symbols that can follow rule ref.

///

 

This seems fairly straightforward at first glance, but then I discovered
that there is no mismatchRecover() function to override. Digging through
the code, I suspect that this function was renamed to
recoverFromMismatchedToken(), but I cannot simply override it with
mismatch() because their prototypes do not match.

 

void        * (*recoverFromMismatchedToken)   (struct
ANTLR3_BASE_RECOGNIZER_struct * recognizer,

                                              ANTLR3_UINT32 ttype,

                                              pANTLR3_BITSET_LIST
follow);

 

void        (*mismatch)                       (struct
ANTLR3_BASE_RECOGNIZER_struct * recognizer,

                                              ANTLR3_UINT32 ttype,

    pANTLR3_BITSET_LIST follow);

 

As you can see, one returns a void *, and the other returns void. What
is the correct way to do this?

 

Thanks,

 

Justin Murray 
Software Engineer 
jmurray at aerotech.com

Aerotech, Inc. 
101 Zeta Drive 
Pittsburgh, PA 15238 
412-963-7470