Re[2]: bison %union and C++

[Oleg Smolsky]

Hello Hans,

Hans Aberg wrote on Wednesday, September 25, 2002:
OS>> here  is  a  question  that  is  probably  asked  for a millionth
OS>> time....
HA> So you have figured it out. :-)
I tried :) But there are no samples that I could find....

OS>> Anyway, with bison 1.49b and C++ skeleton, how do I include a C++
OS>> class  into  the  bison's  types?  In theory, I would like to add
OS>> std::string  into  the  %union section, but this is prohibited by
OS>> ANSI C++.
HA> Just  define  your  own class and YYSTYPE, and don't use unions in
HA> any form.
this is great - thanks! This is exactly what I needed :)

I defined YYSTYPE, typedefed yystype and yyltype, and added a couple
of integer members to the class - everything works great.

I don't need any unions, everything is of one type, and I can do the
following things inside flex:
pObject->m_sData = yytext;
pObject->m_iData = atoi(yytext);
return T_INTEGER;

Thanks a lot - I think this design is much cleaner than the original
union thing. (and guess what - these objects can be stored in c++
containers :)))

Best regards,

Oleg Smolsky
Software Design Authority
Allied Telesyn Research