Beamer vs. Minted: overlays

Question

How to use beamer overlay inside minted code? The obvious solution does not work:

\documentclass{beamer}
\usepackage{minted}

\begin{document}

\begin{frame}[fragile]

\frametitle{Foo}

\begin{minted}{lua}
\uncover<1>{print("foo")}
\uncover<2>{print("bar")}
\uncover<3>{print("baz")}
\end{minted}

\end{frame}

\end{document}

Answer 1

Unfortunately, there is no obvious way to make this work due to the way minted works internally. In fact, it is vital that the code is not parsed by TeX in the usual way.

There might be some trickery possible to circumvent this but for now I suggest that the easiest way to approximate the desired behaviour is to use multiple sequential minted environments:

\uncover<1>{\begin{minted}{lua}
print("foo")
\end{minted}}
\uncover<2>{begin{minted}{lua}
print("bar")
\end{minted}}
\uncover<3>{\begin{minted}{lua}
print("baz")
\end{minted}}

Though to be honest I’m not certain if this even works.

Answer 2

After some trial and error the following is the only solution that works for me:

\begin{frame}

\begin{overprint}
\onslide<1>
\begin{minted}{c++}
   ...
\end{minted}

\onslide<2>
\begin{minted}{c++}
   ...
\end{minted}
\end{overprint}

\end{frame}

Answer 3

I used something similar to what Konrad Rudolph suggested, I used \onslide<n> before the minted block (actually #+begin_src in emacs' orgmode). It does not require curly brackets around the block.

Answer 4

The following worked for me: (I'm using Pygments 1.5 which is pre-release at the moment.)

\begin{frame}[fragile]
  \frametitle{...}

  \begin{minted}{haskell}
    data C a = ...
  \end{minted}

  \begin{minted}{c++}
    template<typename T> class C {...};
  \end{minted}

  \begin{minted}{scala}
    class C[T] {...};
  \end{minted}
\end{frame}

The fragile keyword is in fact what does the trick for me. (Note its use after \begin{frame}.)