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Re: Ignore break line sometimes

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"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'.
>
> To ignore '\n' in the white lines.

I've tried a few schemes. One just converts a newline to a semicolon,
*unless* the last symbol was (for example) a comma.

This requires some sort of continuation symbol for when a semicolon would be
inappropriate.

And it helps if the grammar is tolerant of extra semicolons, otherwise the
source code could be full of continuation symbols! (After 'then' for
example.)

Whatever scheme you choose, you'll know it works well when you have
thousands of lines of code without a single semicolon, and hardly any
continuations.  And that is perfectly clear to read.

--
Bartc

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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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