Re: accessing yyval outside lex and yacc

[Axel Kittenberger]

> Bison implements %union as a C/C++ union, and those unions cannot hold
> data
> of user defined classes (specifically, with their own explicit
> constructors). So if one wants to use such user defined classes, the Bison
> %union feature goes down the drain.

Äooking at c globally I don't see all what 'union' has an advantage against
nomral typecasts, same goes for bison where union is only internally used,
why not simply make directly typecasts at output?

union TOKEN {
  int i;
  char *s;
}

Normally a rule would aprox. look like this:
token1.i = strlen(token2.s);

what's the advantage against having the generator generate:
(int) token1 = strlen( (char *) token2);

Okay fair question would be what's the advantage doing it this way? You'll
save the union defintion, and don't know for sure, would it help for your c++
problems? 

- Axel

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