[Haskell-cafe] Partially applied functions

You can pattern match on the right hand side of '|' in a list comprehension, since a list comprehension is just the list monad. Just changed a few things. Hopefully this answers the OP's question and any interested others. add :: Int - Int - Int add x y = x + y -- a list of partially applied

[Haskell-cafe] Partially applied functions

Hi cafe, Is such a thing possible, add :: Int - Int - Int add x y = x + y -- a list of partially applied functions adds = [add 3, add 5, add 7, add 3, add 5, add 8] -- an example usage of the list k = map (\ f - f 10 ) adds add3s = filter (?) adds -- add3s = [add 3, add 3] addEvens = filter

Re: [Haskell-cafe] Partially applied functions

Ozgur Akgun wrote: Hi cafe, Is such a thing possible, add :: Int - Int - Int add x y = x + y -- a list of partially applied functions adds = [add 3, add 5, add 7, add 3, add 5, add 8] -- an example usage of the list k = map (\ f - f 10 ) adds add3s = filter (?) adds -- add3s =

Re: [Haskell-cafe] Partially applied functions

Sorry, no good. I don't want to guess the first paramater, I really want to access it. 2009/11/28 Steffen Schuldenzucker sschuldenzuc...@uni-bonn.de Ozgur Akgun wrote: Hi cafe, Is such a thing possible, add :: Int - Int - Int add x y = x + y -- a list of partially applied

Re: [Haskell-cafe] Partially applied functions

Answering my own question, one can achieve the goal via doing a lookup, if the number of possible parameters is limited. eg. assume add is a function which can only take Int's from [0..9]. Interestingly, my situation is exactly like this. I think I'll implement such a lookup. The question is

Re: [Haskell-cafe] Partially applied functions

The question is still open though, if somebody has some magic to extract the prameter from an applied function... It isn't possible. Closest solution will be a list of pairs (function,arg) and a special apply function that takes those pairs and apply to function an argument and.them, apply

Re: [Haskell-cafe] Partially applied functions

-- Here's a expansion of the ideas presented for tracking the argument used -- to create a partially applied function: -- -- Based on simple pairs -- add :: Int - Int - Int add x y = x + y addr :: Int - (Int, Int - Int) addr a = (a, add a) -- a list of partially applied functions adds = [addr

Re: [Haskell-cafe] Partially applied functions

Will the following do what you wish? add :: Int - Int - Int add x y = x + y addends = [3,5,7,3,5,8]::[Int] add3s :: [Int] - [Int - Int] add3s addends = map add (filter (3==) addends) k3 :: [Int] k3 = map (\ f - f 10 ) (add3s addends) -- Regards, Casey

Re: [Haskell-cafe] Partially applied functions

Will the following do what you wish? add :: Int - Int - Int add x y = x + y addends = [3,5,7,3,5,8]::[Int] -- P for predicate addPs :: (Int - Bool) - [Int] - [Int - Int] addPs predicate addends = map add (filter predicate addends) kP :: [Int] kP = map (\ f - f 10 ) (addPs (3==) addends) --

Re: [Haskell-cafe] Partially applied functions

On Nov 28, 2009, at 12:01 , Ozgur Akgun wrote: Answering my own question, one can achieve the goal via doing a lookup, if the number of possible parameters is limited. eg. assume add is a function which can only take Int's from [0..9]. Interestingly, my situation is exactly like this. I think

Re: [Haskell-cafe] Partially applied functions

It sounds as if you want to carry some state around for each partially applied function, I think that's in monad territory. A cardinal rule of functional programming is to create new data, whenever possible. -- Regards, Casey ___ Haskell-Cafe mailing

[Haskell-cafe] Partially applied functions

You can pattern match on the right hand side of '|' in a list comprehension, since a list comprehension is just the list monad. add :: Int - Int - Int add x y = x + y -- a list of partially applied functions adds = [add 3, add 5, add 7, add 3, add 5, add 8] -- an example usage of the list kP