Following up to my own post :-{, but after further communication with
Mike Gunter, a good example for why generalising some of the *By
functions List is a good idea was presented, namely that of
deleteFirstsBy
deleteFirstsBy :: (a -> a -> Bool) -> [a] -> [a] -> [a]
generalising it to
delet
Mike Gunter and Sigbjorn Finne propose generalising the type of the
*By functions as follows:
deleteBy :: (a -> Bool) -> [a] -> [a]
deleteFirstsBy :: (a -> b -> Bool) -> [a] -> [b] -> [a]
notElemBy,elemBy :: (a -> Bool) -> [a] -> [a] -- or just stick with any?
lookupBy
Hi!
I was told by Magnus Carlsson and Enno Scholz that my proposal
lookup :: (Eq a, Monad m, MonadZero n) => a -> m (a,b) -> n b
lookup i ps = do (k,v) <- ps
if k==i then return v else zero
isn't well-typed. I'm sorry for this bug. (I cannot access a compiler for
Ha
Maybe you have seen some mail lately on this list about something
called "Haskell 1.3", and wondered
What is this "Haskell 1.3" anyway?,
Can I buy it?,
or
Do I have it?
By compiling and running the following two-module Haskell program, you
will at least get an answer to the last que
Dear friends of Haskell,
a few days ago I asked the question:
> 2) The library proposal does not contain any advanced data structures (yet).
> How would one declare, for example, ordered sets as an instance of
> Monad[Plus]?
Alastair Reid answered as follows:
> Ordered sets are a pro
