Re: Ignore break line sometimes

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From	George Neuner <gneuner2@comcast.net>
Newsgroups	comp.compilers
Subject	Re: Ignore break line sometimes
Date	Sat, 11 Feb 2012 12:59:57 -0500
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On Sat, 11 Feb 2012 06:56:17 -0800 (PST), Geovani de Souza
<geovanisouza92@gmail.com> wrote:

>I'm trying write an parser to my compiler, and I'm interessed
> to ignore the break line (\n) sometimes. E.g:
>
>if true then [\n]
>  foo(); [\n]
>end; [\n]
>
>So, in the first line, the '\n' after 'then' isn't important, but in
>the second "foo();" could replace the need of the semicolon
>to conclude the statement, or still, in the 'end'.
>
>Too ignore '\n' in the white lines.
>
>How can I do this?

IMO making the newlines significant is a really bad idea ... but
leaving that aside I believe the most effective way would be to have
your lexer return a special "end-of-line" code for either semicolon or
newline and make the end-of-line code optional where it need not be.

You don't say whether your parser is handwritten or tool generated (or
which tools) ... so I can't really give an example.

George

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Ignore break line sometimes Geovani de Souza <geovanisouza92@gmail.com> - 2012-02-11 06:56 -0800
  Re: Ignore break line sometimes Hans-Peter Diettrich <DrDiettrich1@aol.com> - 2012-02-11 17:28 +0100
  Re: Ignore break line sometimes George Neuner <gneuner2@comcast.net> - 2012-02-11 12:59 -0500
  RE: Ignore break line sometimes "Karsten Nyblad" <uu3kw29sb7@snkmail.com> - 2012-02-12 09:21 +0100
    Re: Ignore break line sometimes Kaz Kylheku <kaz@kylheku.com> - 2012-02-13 00:16 +0000
  Re: Ignore break line sometimes Stefan Monnier <monnier@iro.umontreal.ca> - 2012-02-12 10:48 -0500
  Re: Ignore break line sometimes Joshua Cranmer <Pidgeot18@verizon.invalid> - 2012-02-12 12:03 -0600
    Re: Ignore break line sometimes Gene Wirchenko <genew@ocis.net> - 2012-02-19 20:57 -0800
      Re: Ignore break line sometimes glen herrmannsfeldt <gah@ugcs.caltech.edu> - 2012-02-20 08:09 +0000
        Re: Ignore break line sometimes arnold@skeeve.com (Aharon Robbins) - 2012-02-23 21:51 +0000
          Re: Ignore break line sometimes "Jonathan Thornburg" <jthorn@astro.indiana.edu> - 2012-02-27 03:49 +0000
  Re: Ignore break line sometimes "BartC" <bc@freeuk.com> - 2012-02-14 00:25 +0000

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