Re: defined YYERROR_VERBOSE, but still got only "parse error"

> s_gherman@yahoo.com (Sorin Gherman) wrote:
>
...
> >I've looked into the code that actully generates the error message:
> >if (count < 5)
> >{
> > count = 0;
> > for (x = (yyn < 0 ? -yyn : 0);
> > x < (sizeof(yytname) / sizeof(char *)); x++)
> > if (yycheck[x + yyn] == x)
> > {
> > strcat(msg, count == 0 ? ", expecting `" : " or `");
> > strcat(msg, yytname[x]);
> > strcat(msg, "'");
> > count++;
> > }
> >}
> >
> >
> >and found out that count == 5 from the beginning; replacing
> >if (count < 5)
> >with
> >if (1)
> >resulted in an informative error message ("expected" ... "or" ...).
> >
> >What's the problem? Do I need to set up other variables as well, or
> >what?
>
> 5 isn't less than 5.
>
> If count==5, then count<5 is FALSE. You changed the semantics.
>
> Sincerely,
>
> Gene Wirchenko


      Well, that was exactly the purpose of my experiment, to change the
semantics and force it to go into that piece of code. Now I realized
that the reason I didn't get the "expected..." part of the error
message was that there were too many alternatives for Yacc at the
point of the error, and the constant 5 is there exactly to prevent
reporting that when more than 5 possible alternative exist.


      Thanks anyway,
      Sorin Gherman

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