Re:Monads are monoids in the category of endofunctors
by OJFord on Friday September 10, 2021 @06:20AM
(#28479630)
> They also need to preserve composition.
> fmap (f . g) == fmap f . fmap g
Can you give an example where that doesn't follow from `map identity f == f`? Assuming of course `f` .. is what I think is called 'pure'? i.e. is deterministic on its input arguments.
> fmap (f . g) == fmap f . fmap g
Can you give an example where that doesn't follow from `map identity f == f`? Assuming of course `f` .. is what I think is called 'pure'? i.e. is deterministic on its input arguments.