[Haskell-beginners] Re: Installing Gtk2hs

Duncan Coutts duncan.coutts at worc.ox.ac.uk
Sun Nov 30 17:33:54 EST 2008

On Sun, 2008-11-30 at 09:08 +0000, Colin Paul Adams wrote:
>     Colin> Now make fails with:
>     Colin> svgcairo/Graphics/Rendering/Cairo/SVG.chs:201:2: Couldn't
>     Colin> match expected type `()' against inferred type `CInt'
>     Colin> Expected type: Render () Inferred type: Render CInt In the

> So I tried changing Render () to Render CInt in four places in
> SVG.chs.

Aye, the cairo C library changed it's API from 1.6 to 1.8. It added an
int return type to several functions that previously returned void.

> Now it installs OK with 6.8.3, and all the demos run.
> I'd have a go at getting it to work with 6.10.1 if I knew what to do.
> It appears the library structure has changed incompatibly (and ghc
> didn't even change its version number - that's pretty bad).

The version of ghc did change of course, 6.8 -> 6.10, but perhaps you
mean the versions of the libraries? They changed also, to reflect the
API changes.

> Is there a document anywhere that details the structure changes?

Yes, the ghc-6.10 release notes.


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