"However, can you clarify why you would argue for type classes over duck/structural typing? You indicate that 'type classes are the way to go' but don't explain

"However, can you clarify why you would argue for type classes over duck/structural typing? You indicate that 'type classes are the way to go' but don't explain why." Like kscaldef said, you know at compiletime if something can quack, and the overhead for doing this is quite small. Haskell: instance Quacker MySpecialDuck where quack = "qqquuuuuuaaaaaakkkkk" "Scala of course does have a form of Type Classes and while they tend to be what I reach for more often than Structural Types in Scala, it doesn't obviate Structural Types completely and I'd be interested in analysis of the diffs." In which cases do you need duck typing? Adding dynamically a method to a class?