On Wed, Mar 16, 2011 at 7:52 AM, Andrew Coppin
Hmm, yes. That will work, but I wonder if there's some way of doing this that doesn't limit the scope of the container to one single span of code...
You can write helper functions which take containers as argument by parameterizing these helper functions over s:
takesTwoContainers :: Container s1 -> Container s2 -> ... takesTwoContainers c1 c2 = ... -- c1 and c2 can be used here
This function could be called like this:
withContainer (\c1 -> withContainer (\c2 -> takesTwoContainers c1 c2)) -- c1 and c2 can be used here
In this example, the scope of the containers is not limited to a single span of code.
What you can't do is write functions such as
foo :: Container x -> (Cursor x, Cursor x)
for example.
I don't follow. foo = cursor &&& cursor Did you mean to have some extra condition on foo that can't be satisfied? Luke