User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101
            Thunderbird/31.1.1
MIME-version: 1.0
Content-type: text/plain; charset=utf-8; format=flowed
Content-transfer-encoding: 7bit
Message-ID:  <544F701F.7030102@nist.gov>
Date:         Tue, 28 Oct 2014 06:29:51 -0400
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: Bruce Miller <bruce.miller@NIST.GOV>
Subject: mathstyle vs amsmath \genfrac
To: LATEX-L@LISTSERV.UNI-HEIDELBERG.DE
Precedence: list
Envelope-To: <rainer.schoepf@GMX.NET>
Status: R

Hi all;
  Not sure whether this is the right place for this
message, but a colleague is using breqn, which
pulls in a lot of l3kernel stuff, and also mathstyle.

Unfortunately, it appears that the package mathstyle
redefines \genfrac with a different argument order
than amsmath. (and worse, wants to be loaded after
amsmath, so you're stuck with the redefinition)

mathstyle's api seems to be:
   \genfrac{style}{open}{close}{thickness}{numer}{denom}
while amsmath's is
   \genfrac{open}{close}{thickness}{style}{numer}{denom}

Is there a good reason for this?

thanks
bruce