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Re: Maintaining scope while parsing C with a YACC grammar

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On Apr 26, 7:22 pm, Robert A Duff <bobd...@shell01.TheWorld.com>
wrote:
> eliben <eli...@gmail.com> writes:
> > [There's a couple of possibilities.  One is to add separate rules for
> > the open and close braces with action code that increments and
> > decrements the nesting level, so you know when you reduce the
> > declaration what scope it is in.  Another is to parse the whole thing
> > into an AST without trying to interpret the symbols other than making
> > pointers to a generic symbol table entry per name, then walk the AST
> > and add the scope and type info.  Perhaps people will have other
> > suggestions. -John]
>
> I strongly recommend the "build a tree" solution.  It might seem like
> a lot of trouble at first, but it will simplify things in the long
> run.
>
> Do all the interesting work during a subsequent walk of the tree.  Or
> multiple walks.

Since it's parsing of C I'm talking about, this approach will have to
somehow handle ambiguity of this kind:

T * x;

This can be either a declaration or a multiplication, depending on
earlier symbol table information (whether T is a type or not).

So are you proposing to build an ambiguous AST that contains *both*
parses and resolve between them in later passes? Or just pick one and
maybe modify it later? Do you have references (papers, books, etc.)
explaining this technique?

Thanks in advance

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Thread

Maintaining scope while parsing C with a YACC grammar eliben <eliben@gmail.com> - 2011-04-25 05:14 -0700
  Re: Maintaining scope while parsing C with a YACC grammar Robert A Duff <bobduff@shell01.TheWorld.com> - 2011-04-26 12:22 -0400
    Re: Maintaining scope while parsing C with a YACC grammar Robert A Duff <bobduff@shell01.TheWorld.com> - 2011-04-26 14:08 -0400
    Re: Maintaining scope while parsing C with a YACC grammar eliben <eliben@gmail.com> - 2011-04-28 23:20 -0700
      Re: Maintaining scope while parsing C with a YACC grammar Robert A Duff <bobduff@shell01.TheWorld.com> - 2011-05-02 20:19 -0400
        Re: Maintaining scope while parsing C with a YACC grammar "Ira Baxter" <idbaxter@semdesigns.com> - 2011-05-13 17:46 -0500
        Maintaining scope while parsing C with a Yacc grammar Chris F Clark <cfc@shell01.TheWorld.com> - 2011-06-12 20:43 -0400
      Re: Maintaining scope while parsing C with a YACC grammar torbenm@diku.dk (Torben Ægidius Mogensen) - 2011-05-03 09:51 +0200
  Re: Maintaining scope while parsing C with a YACC grammar Paul B Mann <paul@paulbmann.com> - 2011-05-06 10:43 -0700

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