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Thread-Topic: \tlist_head_iii:n "health warning"
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Date:         Thu, 29 Jan 2009 23:07:18 +0100
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From: "Mittelbach, Frank" <frank.mittelbach@EDS.COM>
Subject: AW: \tlist_head_iii:n "health warning"
To: LATEX-L@LISTSERV.UNI-HEIDELBERG.DE
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Status: R

I wonder if we might want the concept of _unsafe functions, ie those that do not check but expect the programer to take care of that, while by default all others will be safe. In certain applications I could see speed/processing reasons for something like this. On the other hand one can question how much this matters these days.

opinions?

frank

-----Ursprüngliche Nachricht-----
Von: Mailing list for the LaTeX3 project [mailto:LATEX-L@LISTSERV.UNI-HEIDELBERG.DE] Im Auftrag von Will Robertson
Gesendet: Donnerstag, 29. Januar 2009 22:55
An: LATEX-L@LISTSERV.UNI-HEIDELBERG.DE
Betreff: Re: \tlist_head_iii:n "health warning"

On 30/01/2009, at 7:10 AM, Joseph Wright wrote:

> It occurs to me that the tlist head functions could do with a health 
> warning.  For example, try:
>
> \tlist_head_iii:n{1}
>
> The documentation doesn't explicitly say that you need to check first 
> that the tlist is sufficiently long.

I'd probably propose that it would be better if the function performed the check itself, or if the tlist were padded with empties or (probably not) \q_no_value's to prevent the error?

W