[Haskell-beginners] trying to install libraries for Haskell School of Expression

[Thomas Bach]

DJ <jakep at arqux.com> writes:

> Graphics/SOE/Gtk.hs:94:18:
> Could not find module `System.Time'
> It is a member of the hidden package `old-time-1.1.0.1'.
> Perhaps you need to add `old-time' to the build-depends in your .cabal
> file.

That is actually all you have to do: in the cabal file of your package
you have either a 'library' section or an 'executable' section. These
should have a field 'build-depends' simply add 'old-time >= 1.1 && <
1.2' their.

See for example the cabal file of the lens package:
https://github.com/ekmett/lens/blob/master/lens.cabal

If you don't have a cabal file you can initialize one via 'cabal init'
or simply install the package in the sandbox via running 'cabal install
old-time-1.1' in your sandbox, i.e. the directory you ran 'cabal sandbox
init' beforehand.


Regards
        Thomas.