Ben Rudiak-Gould wrote:
Brian Hulley wrote:
Is there a reason for using instead of
[exists a. Resource a=a]
?
Only that = looks like a function arrow, looks like a tuple. I
stole this notation from an unpublished paper by SimonPJ et al on
adding existential quantification to
On Fri, Mar 17, 2006 at 04:53:42PM +, Ben Rudiak-Gould wrote:
Matthias Fischmann wrote:
and now it gets interesting: i need instances for Rs on Show, Read,
Eq, Ord. Show is very simple, but Read?
I think you're right: it's impossible to implement Read for Rs in an
extensible way,
Matthias Fischmann wrote:
is there any difference between these
two? if they are equivalent, why the two different ways to say it?
data X where X :: (Resource a) = a - X
data Y = forall a . (Resource a) = Y a
There's no difference. There are two ways to say it for historical reasons.
