Re: Multiple Parsers

[Jonathon Duerig]

On Sun, 16 Mar 2003 address@hidden wrote:

>     It is required that I have multiple parsers that use the same lexer
> in my project. I am aware of the prefixing notation that would enable
> having multiple parsers/lexers but paired with the same names, and bison
> considers the lex to be prefixed same as the parser spec. And I need to
> be able to invoke each parsers individually. Is there a provision
> natively available in bison/flex to do the above.

I'm not sure if there is native support for it, but you could do a simple
forwarding function. It is assumed that this is in combination with the
prefix option.

/* aparse.y */
%{

#include "RealLexer.h"

%}

/* Bison Stuff */
%%
%%
int ayylex(void)
{
    realLex();
    ayylval = getRealLexSemanticValue();
    return getRealLexSyntacticValue();
}

And you could do something similar for bparse.y, cparse.y, etc.

In this case, I'm assuming that the parsing runtimes don't overlap, so it
is set up as a simple module. But one could easily convert to sending
around pointers to structs or whatnot if the thing needs to be reentrant.

Hope this helps.

---
Most of what I read is fiction, but the authors don't admit it.
    -Jonathon Duerig