Scala for Haskell programmers
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Scala for Haskell programmers
1–6 of 6 posts
Re: Scala for Haskell programmers
#2It reads somewhat like "The Occult for The Arcane", doesn't it?
Re: Scala for Haskell programmers
#3Scala is definitely one of the better functional languages for Java. (It's OO implementation is not that great, however.)
I am left with a few questsions:
Monoid was used as an example, but does Scala's type system support instances like:
instance (Monoid a, Monoid b) => Monoid (a,b) where
mempty = (mempty, mempty)
...
(I ask, because I wrote a Haskell-style data structure module for Perl, but it is missing Monoid for this reason. We would know the types after mempty ran, but we can't run it without knowing the types. If only you could fold time back on itself...)
Also, they use the word "forAll" to describe type signatures; are higher-rank types allowable?
Re: Scala for Haskell programmers
#4It reads somewhat like "The Occult for The Arcane", doesn't it?
Perhaps if you don't know Haskell, Scala, or any computer science beyond "trees"...
Re: Scala for Haskell programmers
#5[deleted]
Re: Scala for Haskell programmers
#6Scala is definitely one of the better functional languages for Java. (It's OO implementation is not that great, however.) I am left with a few questsions: Monoid was used as an example, but does Scala's type system support instances like: instance (Monoid a, Monoid b) => Monoid (a,b) where mempty = (mempty, mempty) ... In this case, a mempty tuple is created by creating a mempty "a" and then a mempty "b". If you thin…
No higher-rank types in Scala, I'm afraid.
As for the monoid instance:
def pairMonoid[A,B](a:Monoid[A],b:Monoid[B]) = new Monoid[(A, B)] { def empty = (a.empty, b.empty) ... }