Mercurial > repo
view interps/rhotor/Misc.hs @ 4155:1e4bcd213420
<oerjan> echo \'A catamorphism is when you recurse too greedily and too deep.\' >wisdom/catamorphism
author | HackBot |
---|---|
date | Tue, 10 Dec 2013 17:18:55 +0000 |
parents | 859f9b4339e6 |
children |
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module Misc ( stringToNodeTree, nodeTreeToString, numberToNodeTree, nodeTreeToNumber, apply ) where import Node stringToNodeTree :: String -> Node stringToNodeTree "" = Nil stringToNodeTree (c:t) = Cons (numberToNodeTree (fromEnum c)) (stringToNodeTree t) nodeTreeToString :: Node -> String nodeTreeToString Nil = "" nodeTreeToString (Cons a b) = (toEnum (nodeTreeToNumber a):nodeTreeToString b) numberToNodeTree :: (Integral a) => a -> Node numberToNodeTree 0 = Nil numberToNodeTree (n+1) = Cons Nil (numberToNodeTree n) nodeTreeToNumber :: (Integral a) => Node -> a nodeTreeToNumber Nil = 0 nodeTreeToNumber (Cons Nil a) = (nodeTreeToNumber a) + 1 apply :: Node -> Node -> Node apply a b = (Application a b)