References: <55A8C0C2.3040908@morningstar2.co.uk>
            <20150717095912.GA6487@hzdr.de>
            <55A8E267.1030901@morningstar2.co.uk>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-15
Content-Disposition: inline
User-Agent: Mutt/1.5.23 (2014-03-12)
Message-ID:  <20150717140025.GA10619@hzdr.de>
Date:         Fri, 17 Jul 2015 16:00:25 +0200
Reply-To: Mailing list for the LaTeX3 project
              <LATEX-L@LISTSERV.UNI-HEIDELBERG.DE>
Sender: Mailing list for the LaTeX3 project <LATEX-L@LISTSERV.UNI-HEIDELBERG.DE>
From: Alexander Grahn <A.Grahn@HZDR.DE>
Subject: Re: expl3 boolean expressions: lazy evaluation
To: LATEX-L@LISTSERV.UNI-HEIDELBERG.DE
In-Reply-To:  <55A8E267.1030901@morningstar2.co.uk>
Precedence: list
Envelope-To: <rainer.schoepf@GMX.NET>
Status: R

Joseph,

On Fri, Jul 17, 2015 at 12:09:27PM +0100, Joseph Wright wrote:
>by
>
>    \bool_if:nTF
>      {
>        !\cs_if_exist:cTF {#1}
really an `!' in front?

>by
>
>    \bool_if:nT
>      {
>        ! \cs_if_exist:NTF \fxocg@insert@OC
same here.

>which could be redone as for the first case in media9. However,
>reviewing the code I realise that as you have \use:c here you'll
>actually get away with it (the second part will evaluate even if the
>csname is undefined). If you do want a 'safe' change then
>
>    \bool_if:nTF
>      {
>        ! \cs_if_exist:cTF { OCGpdfobj#3 }
same here.

Alexander