I can't get the following to work in Leksah - but it works OK in GHC.
Can anyone spot the error?
I wondered if it was becasue the libraries loaded are different - but
I'm just a Haskell beginner ...
I have:
myGroupBy :: Int→ [a]→ [[a]]
myGroupBy = takeWhile not . null . (unfoldr (Just .
I'm trying:
instance Num b = Num (a - b) where
fromInteger = pure . Prelude.fromInteger
negate = fmap Prelude.negate
(+) = liftA2 (Prelude.+)
(*) = liftA2 (Prelude.*)
abs = fmap Prelude.abs
signum = fmap Prelude.signum
but the compiler rejects it with:
src\Main.hs:24:9:
Could not deduce
with it for the foreseeable future.
On Sat, Oct 31, 2009 at 7:31 PM, b1g3ar5 nick.st...@gmail.com wrote:
I'm trying:
instance Num b = Num (a - b) where
fromInteger = pure . Prelude.fromInteger
negate = fmap Prelude.negate
(+) = liftA2 (Prelude.+)
(*) = liftA2 (Prelude.*)
abs
I have a list of people not on their own list.
I can't decide whether I should be on it or not.
On Oct 1, 6:38 pm, Daniel Peebles pumpkin...@gmail.com wrote:
I try to keep my list up to date with new haskellers I find on twitter, and
it should include everyone on the haskell wiki list. Yes,
I've tried to solve this but I am failing.
I can do this:
p0-panel nb []
e0-textCtrl p [text:=my_list!!0]
but I want to do this on all of my_list, so I tried:
let es = map (\x- textCtrl (panel nb []) [text:=x]) my_list
Now, this won't work because the panel nb [] is IO (Panel()) and the
:21 pm, Daniel Fischer daniel.is.fisc...@googlemail.com
wrote:
On Friday 07 January 2011 17:09:11, b1g3ar5 wrote:
I've tried to solve this but I am failing.
I can do this:
p0-panel nb []
e0-textCtrl p [text:=my_list!!0]
but I want to do this on all of my_list, so I tried:
let es
...@googlemail.com
wrote:
On Friday 07 January 2011 19:01:43, b1g3ar5 wrote:
Thanks for your reply but it doesn't quite solve the problem. This:
plist - mapM (\x- (panel nb [])) my_list
returns [Panel()] and works as you say, but:
elist - mapM (\x- (textCtrl (panel nb []) [text
2011 19:45:26, b1g3ar5 wrote:
Nearly - the first suggestion doesn't work because each es needs a new
panel I can't use the same one each time.
The second suggestion doesn't quite work because the x in [text :=
contents x] is not in scope of the \p function.
Hmm,
Prelude Graphics.UI.WX
