haskell - Interfaces in functional programming -


in java , c# have interfaces, equivalent in language haskell or concept called in functional programming?

there things typeclasses, other answers say, more that, there's 1 pervasive interface: a function. many, many places object-oriented program need custom interface, similar functional program can use function. eg, map f xs in haskell uses f, object-oriented program might use visitor or whatever accomplish same task.


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