[Haskell-beginners] Issue installing reactive-banana-5.0.0.1

[Heinrich Apfelmus]

Miguel Negrao wrote:
> 
> Since I have wxWidgets 2.9.3 installed already I might as well give
> it a try with reactive-banana-0.6. I installed wx-0.90 and
> wxcore-0.90 and reactive-banana-0.6.0 (from git) without issues. I
> couldn’t install reactive-banana-wx though, I get this error:
> 
> Configuring MissingH-1.1.1.0...
> Warning: This package indirectly depends on multiple versions of the same
> package. This is highly likely to cause a compile failure.
> package regex-base-0.93.2 requires mtl-2.0.1.0
> package parsec-3.1.1 requires mtl-2.0.1.0
> package parsec-3.1.1 requires mtl-2.1
> package hslogger-1.1.5 requires mtl-2.1
> package MissingH-1.1.1.0 requires mtl-2.1
> package MissingH-1.1.1.0 requires parsec-3.1.1
> package network-2.3.0.5 requires parsec-3.1.1
> package mtl-2.0.1.0 requires transformers-0.2.2.0
> package mtl-2.1 requires transformers-0.3.0.0
> Preprocessing library MissingH-1.1.1.0...
> Preprocessing executables for MissingH-1.1.1.0...
> Building MissingH-1.1.1.0...
> <command line>: cannot satisfy -package-id parsec-3.1.1-178bb186a8cbec1a8bf6b3192212c18e: 
>    parsec-3.1.1-178bb186a8cbec1a8bf6b3192212c18e is shadowed by package parsec-3.1.1-fb91ea6e6c1f9c50292782ec985e5f9a
>    (use -v for more information)
> Updating documentation index
> /Users/miguelnegrao/Library/Haskell/doc/index.html
> cabal: Error: some packages failed to install:
> MissingH-1.1.1.0 failed during the building phase. The exception was:
> ExitFailure 1
> cabal-macosx-0.2 depends on MissingH-1.1.1.0 which failed to install.
> reactive-banana-wx-0.6.0.0 depends on MissingH-1.1.1.0 which failed to
> install.

Fortunately, this time it's not my fault. :)

You ran into a cabal problem with a package depending on multiple 
versions of the same package. The culprit seems to be  regex-base . I 
suggest you try

     cabal install regex-base parsec-3.1.1 \
         --reinstall --constraint='mtl == 2.1'

to resolve this issue. Then try installing  reactive-banana-wx  again.


> ps: Does reactive-banana also have time functions like it is
> described in conal’s papers ? i.e. can I just animate something with
> a function like cos (t) or do I have to explicitly create timers
> myself ?

No, you have to create timers yourself. It's not very difficult, though, 
you can just create a wxWidget and listen to its  command  event.


Best regards,
Heinrich Apfelmus

--
http://apfelmus.nfshost.com