Javascript to Elm
61: Getting Haskell Unit 2 (TypeClasses)
- Author: Vários
- Narrator: Vários
- Publisher: Podcast
- Duration: 0:23:11
- More information
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Synopsis
Follow up Elm does not currently support type classes. Does it need to? Using TypeClasses Implement your own type classes Understand polymorphism in Haskell `Know when to use deriving Search for documentation with Hackage and Hoogle Show class Show a where show :: a -> String turns any value into a string for output So the output we see from GHCI automatically derived typeclass Vanillia | Chocolate Ord class Eq a => Ord a where compare :: a -> a -> Ordering ( a -> Bool ( a -> Bool (>) :: a -> a -> Bool (>=) :: a -> a -> Bool max :: a -> a -> a min :: a -> a -> a Cool, Ord is defined as a Eq class. oh that’s rad well i guess if you’re gonna order something you’ll need to compare it’s equally, just like it says in the the compare definition. compare :: Ord a => a -> a -> Ordering man it makes so much sense it’s a bit frightening. EQ class Eq a where (==) :: a -> a -> Bool (/=) :: a -> a -> Bool pretty straight forward takes, 2 values and returns a bool, True or False