[Gtk2hs-devel] [PATCH] Bug fixes for treeModelFilterSetVisibleFunc and treeSortableSetDefaultSortFunc

[Maxime H. <mhe...@gm...>]

	Hello all,


The attached patch fixes a few minor problems in the gtk package.

The treeModelFilterSetVisibleFunc function was accepting a "Maybe
(TreeIter -> IO Bool)" type for the visible function, allowing to pass
NULL to the corresponding gtk function when Nothing had been given.
However, this isn't supported by the gtk API and causes an error message
to be printed about it on the console.  I just changed the type to a
plain "TreeIter -> IO Bool" and removed the Nothing case.

In a surprisingly symmetrical way, the treeSortableSetDefaultSortFunc
was only accepting a "TreeIter -> TreeIter -> IO Ordering" type for the
sort function, whereas this time, it is possible to pass NULL to the
underlying gtk function.  Doing so is actually quite useful: it allows
to disable the "original" ordering of your rows.  If you don't do that,
clicking on a column header cycles through ascending sort, descending
sort, *and* original order.  Passing a NULL default sort function allows
to have only the 2 usual sorting states.

Needless to say, both fixes break the API, and I am not sure how you
guys handle these kind of things.

Thanks!
Maxime Henrion