Message-Id: <199402081711.AA21159@mail.cs.tu-berlin.de>
Reply-To: Mailing list for the LaTeX3 project <LATEX-L@DHDURZ1.BITNET>
In-Reply-To:  <9402081657.AB10089@m1.cs.man.ac.uk> (dmjones@THEORY.LCS.MIT.EDU)
Date:         Tue, 8 Feb 1994 17:09:07 GMT
From: David Carlisle <carlisle@cs.man.ac.uk>
Sender: Mailing list for the LaTeX3 project <LATEX-L@DHDURZ1.BITNET>
To: Multiple recipients of list LATEX-L <LATEX-L@DHDURZ1.BITNET>
Subject:      Re: additional features
Status: R

>>>>> "David" == David M Jones <dmjones@THEORY.LCS.MIT.EDU> writes:

>> Date: Fri, 4 Feb 1994 18:34:54 +0100 From: "J%org Knappen, Mainz"
>> <KNAPPEN@VKPMZD.KPH.UNI-MAINZ.DE>
>>
>> I was afraid the answer would be ,,no''. I have thought about the
>> problem some time, but I dismissed all possible syntaxes coming to
>> my mind (like employing a third type of braces).

David> My apologies if this has already been asked, but what's wrong
David> with using a 3rd type of brace?  LaTeX already uses parentheses
David> to delimit arguments in some cases, so this isn't even a
David> complete innovation.

David> David.

The original comment is in response to my comment that adding a new
optional argument at the end of a command could break existing
documents, that might start a section with `['.

As I have already indicated to J"org Knappen directly, this argument
only really applies to adding new functionality to the core.

It must surely be safe to add optional arguments via an extension
package. This will never break existing documents, and the
documentation for the package can say that with this package, to
start a section with [ (if you have not used the last optional
argument for \section) then you must use \literal{[}.

LaTeX has a clear concept that optional arguments should go in [], and
I think that introducing other delimiters for optional arguments would
not be a good idea.

David (a different one)