Zulip Chat Archive
Stream: general
Topic: Is this monad equation true?
François G. Dorais (Dec 04 2024 at 00:12):
Is this true?
[Monad m] [LawfulMonad m] (f : m α → m β) (x : m α) : x >>= f ∘ pure = f x
I would love a proof if it is true.
François G. Dorais (Dec 04 2024 at 00:19):
Never mind. I found a counterexample right after pressing enter...
Mario Carneiro (Dec 04 2024 at 13:39):
this depends on some property of f
, it's related to monotonicity in the domain theory sense
Mario Carneiro (Dec 04 2024 at 13:42):
or maybe lower semicontinuity, since it's saying that f x
is the supremum of f (pure a)
over all a <= x
Last updated: May 02 2025 at 03:31 UTC