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Re: Articles/books that discuss separating the context-free part of a language from the context-sensitive part?

From Gene Wirchenko <genew@telus.net>
Newsgroups comp.compilers
Subject Re: Articles/books that discuss separating the context-free part of a language from the context-sensitive part?
Date 2013-05-19 18:02 -0700
Organization A noiseless patient Spider
Message-ID <13-05-015@comp.compilers> (permalink)
References <13-05-010@comp.compilers> <13-05-011@comp.compilers>

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On Sat, 18 May 2013 00:18:54 +0000 (UTC), glen herrmannsfeldt
<gah@ugcs.caltech.edu> wrote:

[snip]

>As I remember it, it is not so easy to do for recursive descent
>parsers. As a result, as noted, you get poor error messages, such as:
>
>   SYNTAX ERROR
>
>somewhere near where the problem is. For languages with reserved works,
>it is nice to say exactly what the problem is. It gets more

     It is nice for any language.  When parsing string, I tend to
avoid complex regexes for the same reason.  If I build an FSA, I can
often get specific on what the error is.

>interesting without reserved words. Yesterday, following a post
>in comp.lang.fortran I tried:
>
>TYPE :: DEEP
>   TYPE(DEEP) :: POINTER
>END TYPE
>
>When compiling it, the error message, pointing right to the
>word POINTER, say "must have POINTER attribute".
>
>Fortunately it only took me a few seconds to figure out, and then
>laugh at it. But yes, you can get funny messages without reserved
>words.

     Could you explain what the error was?  I do not know modern
Fortran.

Sincerely,

Gene Wirchenko

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Thread

Articles/books that discuss separating the context-free part of a language from the context-sensitive part? "Costello, Roger L." <costello@mitre.org> - 2013-05-17 20:57 +0000
  Re: Articles/books that discuss separating the context-free part of a language from the context-sensitive part? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2013-05-18 00:18 +0000
    Re: Articles/books that discuss separating the context-free part of a language from the context-sensitive part? Gene Wirchenko <genew@telus.net> - 2013-05-19 18:02 -0700
      Re: Articles/books that discuss separating the context-free part of a language from the context-sensitive part? glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2013-05-20 03:17 +0000
  Re: Articles/books that discuss separating the context-free part of a language from the context-sensitive part? Aleksey Demakov <ademakov@gmail.com> - 2013-05-18 16:52 +0400
  Re: Articles/books that discuss separating the context-free part of a language from the context-sensitive part? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-05-20 10:53 +0000
    Re: Articles/books that discuss separating the context-free part of a language from the context-sensitive part? Gene Wirchenko <genew@telus.net> - 2013-05-20 23:24 -0700
    precedence have both ways jgk@panix.com (Joe keane) - 2013-05-30 23:21 -0400
      Re: precedence have both ways glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2013-05-31 05:10 +0000
      Re: precedence have both ways anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-05-31 10:54 +0000

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