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Re: RFC: multiline comments

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From:
Glenn Linderman
Date:
August 3, 2000 18:32
Subject:
Re: RFC: multiline comments
Message ID:
398A1D86.BC22FA9@Linderman.com
Michael Mathews wrote:

> [I've cc'd your comment to the MLC sublist]

I've still got nothing from it, as yet.

> Glenn Linderman pointed out:
> > I think you missed something in reading my proposal, perhaps you thought
> my #<<
> > and #< syntaxes were alternatives?  I see them as working together, one
> for
> > multi-line comments and one for in-line comments, with # for end-of-line
> > comments.
> >
> > I'd rewrite your example below, as
> > code here;
> > #<<END_OF_COMMENT
> >     # this is a single line comment
> >     $foo = $a + $b #< here's an in-line comment ># + $c * $d;
> > END_OF_COMMENT
> > more code here;
>
> Ooohh...!!! I see now.
>
> However I fail to see the need for both. Can you give an example of where I
> could'nt use #<...># in place of #<< ?

Well, if you vote my way on my comments in my original message on this topic, #<
># would be intentionally restricted to 1 line; hence any time you want a
multiline, you couldn't use #< >#.  The reasoning behind it was that if <
already appears as the first character in some existing comments, that the
compiler could catch it by the end of the line, and have a good likelihood of
not executing the script with the erroneous interpretation of the comment.

The "#<<token" syntax was perceived to be (1) too verbose for in-line comments,
(2) long enough that it wasn't likely to appear in an existing comment by
accident, and (3) the likelihood of finding 'token' at the beginning of a line
to satisfy the compiler without error if it did appear in an existing comment
would be extremely low.

These 3 points don't hold for #< >#.

> BTW: I've been playing and I found that this looks cool and also works under
> perl5:
>
> <<'#';
>    some commented lines
> #
>
> so your #<< sytax enjoys the benefit of looking a lot like Perl!
>
> --Michael

This being the "string in a void context" concept that someone else wanted to
have printed to the default output filehandle...

--
Glenn
=====
There  are two kinds of people, those
who finish  what they start,  and  so
on...                 -- Robert Byrne



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