How does one go about doing doubly linked lists in a pure functional language? That is, something like Haskell where you\'re not in a Monad so you don\'t have mutation. Is it possible? (Singly linked
can anybody help me understand this code solve s | s == 0 = Nothing s == 1 = Just 1 otherwise = 开发者_开发问答check [solve (s-(x*2)) | x <- [1..9]]
In Andrew Koenig’s An anecdote about ML type inference, the author uses implementation of merge sort as a learning exercise for ML and is pleased to find an “incorrect” type inferenc
I just realized how useful the little on-function can be. Ex: orderByLength = sortBy (compare `on` length)
I know GHCi supports Readline, and keybindings such as ^Wand ^U开发者_运维知识库 work as expected.
There is a list L. It contains elements of arbitrary type each. How to delete all duplicate elements in such list efficiently? ORDER must be preserved
When working with monadic expressions in Haskell, the use of liftM\'s (even in infix position)开发者_如何学JAVA often seems quite unaesthetic and verbose to me.
I want to create my own monad. This is what i wrote: data LeafConType a = LeafCon (a,In开发者_运维知识库t,Int)
In Haskell, is there a way to compare that all wildcards are of the same type and value? For example, I want to create a function that exhibits the following behavior:
tick :: State Int Int tick = get >>= \\n -开发者_如何学C> put (n+1) >>= \\y -> return n
加载中,请稍侯......