doc: \pause can mess up tikzpictures

[hmenke]

See for example:

• https://tex.stackexchange.com/questions/21512/pause-in-tikzpicture-breaks-footline

[samcarter]

@hmenke Thanks for the PR!

[josephwright]

I'm not so sure about this - TIll after all wrote both beamer and pgf and in general you can use \pause inside TikZ structures - the amsmath situation is very different.

[samcarter]

I'm not so sure about this - TIll after all wrote both beamer and pgf and in general you can use \pause inside TikZ structures - the amsmath situation is very different.

footlines etc. will vanish

[josephwright]

Sure but that's an edge case - you cannot use \pause in amsmath structures at all, really.

[samcarter]

@josephwright We could experiment with patching the end of the tikzpicture, e.g. \AtEndEnvironment{tikzpicture}{\onslide<1->} and see if it breaks something...

[samcarter]

I think the situation for amsmath is really similar to tikzpictures. Sometimes \pause might work, sometimes it might give wrong results.

E.g. a user might get away with something like

\documentclass{beamer}
\mode<presentation> { \setbeamercovered{transparent} }

\begin{document}
\begin{frame}
\begin{align}
  A &= B \\\pause
    &= C \\\pause
    &= D
\end{align}
\end{frame}
\end{document}

because they are lucky and happen to use the right uncover setting. They might also get away with using \pause in tikzpictures if they don't have a footline. But in general, \pause can cause problems.

[samcarter]

(@josephwright If you feel strongly about this, I'm fine with rolling back the commit. People will anyway keep trying to use it - the difference will just be if my answers on Q&A sites will be "don't use \pause" or "don't use \pause, see the doc" :) )

[samcarter]

@josephwright Would you prefer if I would roll back the commit or do we keep it?