Re:Monads are monoids in the category of endofunctors
by kortex on Friday September 10, 2021 @12:08AM
(#28477714)
You remind me of when I started to actually get this stuff and it occurred to me that monads are just metadata+data with some special properties, and I posted about it on reddit and got downvoted to hell and told the many ways how that's wrong. The FP crowd...must be great at parties. I get this frustration.
I think a big part of it is difference in definitions. There's the mathematician's monad, which is pure and abstract and obeys all these laws. And then there's the engineer's monad: an interface you can map, ap, and flatmap over. People get so hung up over "algebraic purity" they forget why they were invented/co-opted for software in the first place: to solve the problem of applying pure functions to side-effecty operations.
> A monad is a wrapper. Anyone who tells you otherwise is being obtuse.
I think a big part of it is difference in definitions. There's the mathematician's monad, which is pure and abstract and obeys all these laws. And then there's the engineer's monad: an interface you can map, ap, and flatmap over. People get so hung up over "algebraic purity" they forget why they were invented/co-opted for software in the first place: to solve the problem of applying pure functions to side-effecty operations.
> A monad is a wrapper. Anyone who tells you otherwise is being obtuse.
https://rcrowley.org/2011/09/21/monads.html