[wxhaskell-users] assert that WX.start is run exactly once

[Henning T. <le...@he...>]

Sometimes I forget to enclose a WX-GUI in WX.start, now I have a case, 
where WX.start was called twice at different places.

How about putting the WX commands in a separate monad and give WX.start 
the signature:

WX.start :: WX a -> IO ()

?