What's the point of 'const' in the Haskell Prelude?

Question

Looking through the Haskell Prelude, I see a function const:

const x _ = x

I can\'t seem to find anything relevant regarding t

Answer 1

Another use is to implement class member functions that have a dummy argument which should not be evaluated (used to resolve ambiguous types). Example that could be in Data.bits:

instance Bits Int where
  isSigned = const True
  bitSize  = const wordSize
  ...

By using const we explicitly say that we are defining constant values.

Personally I dislike the use of dummy parameters, but if they are used in a class then this is a rather nice way of writing instances.