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Re: How to parse attributes?

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Philipp Klaus Krause <pkk@spth.de> writes:

> I guess the main problem is that I am not really familiar with lex /
> yacc. The situation with the attribute is a bit different from string
> literals though:
>
> 1) Inside a string literal, everything is just text. The inside of the
> attribute still should be tokenized.

... and parsed.

> 2) [ is atoken that has many uses in C. We don't really know we're in an
> attribute while in lex, that knowledge is only there yacc.

It would have been simpler to handle if [[ had been made a new
punctuator.  That would not be odd; both + and ++ are distinct tokens.
However, it seems an attribute specification starts with two separate [
tokens, so if you need to use lex start conditions to alter the lexing
inside [[ and ]], you will need to use a yacc action to trigger that.
Ask in a yacc/bison group to get the details.

But I am not 100% sure you have to do this.  What is your source for
keywords being regarded as identifiers?  In the usual C grammar, the
rule for "identifier" is very general (the usual letters and digits
definitions), but keywords are considered to be a separate category.
Thus the grammar item "identifier" really means "things that have the
right form but which aren't keywords".

-- 
Ben.

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Thread

How to parse attributes? Philipp Klaus Krause <pkk@spth.de> - 2019-11-20 09:41 +0100
  Re: How to parse attributes? David Brown <david.brown@hesbynett.no> - 2019-11-20 10:05 +0100
    Re: How to parse attributes? Philipp Klaus Krause <pkk@spth.de> - 2019-11-20 11:05 +0100
      Re: How to parse attributes? David Brown <david.brown@hesbynett.no> - 2019-11-20 12:35 +0100
  Re: How to parse attributes? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-20 11:06 +0000
  Re: How to parse attributes? Öö Tiib <ootiib@hot.ee> - 2019-11-20 23:16 -0800
    Re: How to parse attributes? Philipp Klaus Krause <pkk@spth.de> - 2019-11-21 10:39 +0100
      Re: How to parse attributes? Öö Tiib <ootiib@hot.ee> - 2019-11-21 02:51 -0800
        Re: How to parse attributes? James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-11-21 05:00 -0800
      Re: How to parse attributes? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-22 02:21 +0000
        Re: How to parse attributes? Keith Thompson <kst-u@mib.org> - 2019-11-21 20:41 -0800
          Re: How to parse attributes? Philipp Klaus Krause <pkk@spth.de> - 2019-11-22 09:15 +0100
          Re: How to parse attributes? David Brown <david.brown@hesbynett.no> - 2019-11-22 09:48 +0100
            Re: How to parse attributes? "A. K." <minforth@arcor.de> - 2019-11-22 02:00 -0800
              Re: How to parse attributes? David Brown <david.brown@hesbynett.no> - 2019-11-22 11:41 +0100
              Re: How to parse attributes? Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-11-24 14:02 +0000
                Re: How to parse attributes? raltbos@xs4all.nl (Richard Bos) - 2019-11-25 16:21 +0000
            Re: How to parse attributes? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-22 17:46 +0000
              Re: How to parse attributes? Keith Thompson <kst-u@mib.org> - 2019-11-22 10:53 -0800
                Re: How to parse attributes? Ben Bacarisse <ben.usenet@bsb.me.uk> - 2019-11-23 00:08 +0000
    Re: How to parse attributes? scott@slp53.sl.home (Scott Lurndal) - 2019-11-21 15:57 +0000
    Re: How to parse attributes? Bonita Montero <Bonita.Montero@gmail.com> - 2019-11-22 08:21 +0100
    Re: How to parse attributes? Bart <bc@freeuk.com> - 2019-11-22 12:11 +0000

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