Hi, a java-programmer running into trouble while trying to learn Haskell. I try to make a hash containing hashes but can not getting a value out of the innermost hash - I keep running into type-trouble where IO and Maybe monad is getting mixed?
My attempt: removeMaybeHash x = case x of Just ref -> ref Nothing -> HashTable.new (==) (\key -> key) test = do h <- HashTable.new (==) (\key -> key) h1 <- HashTable.new (==) (\key -> key) HashTable.insert h 3 h1 HashTable.insert h1 1 1000 maybeOuterHash <- HashTable.lookup h 3 res <- removeMaybe (removeMaybeHash maybeOuterHash) 1000 return res Any clues? In java this would be as simple as (pseudocode): h.lookup(3).lookup(1000) Cheers, Pedro
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