4 ms·

Javascript programmers seem to have no problem using a monad every day (promises), and they are huge fans of do-notation in the from of async/await. Imperative

Javascript programmers seem to have no problem using a monad every day (promises), and they are huge fans of do-notation in the from of async/await. Imperative programmers do not seem to have an issue with the idea of assignment, why are monads problematic? By "combinator" do you mean combinator as in the combinator pattern? I have no idea what value your comment brings us except a way for people who already agree with you to give you upvotes, and what's the point in that?

jowiar 7y ago
The big issue with Haskell isn’t the concepts — it’s the syntax. ASCII art as code is an abomination. Being unable to read code upon first glance it makes it inaccessible.
jes5199 7y ago
getting people who already agree with me to give me upvotes is the whole point of this website
AnimalMuppet 7y ago
> Imperative programmers do not seem to have an issue with the idea of assignment, why are monads problematic? This drive-by-question style makes it hard for me to know what your real point is. Are you saying that an assignment does the same thing as a monad? OK. That it is a monad? I doubt it; assignment doesn't have the right operators (you might argue that it does, but you'd have to really stretch it.) That it's just as simple and easy to understand as a monad? I call BS. > I have no idea what value your comment brings us except a way for people who already agree with you to give you upvotes, and what's the point in that? That kind of rhetoric is against the site guidelines.
dragonwriter 7y ago
> Javascript programmers seem to have no problem using a monad every day (promises) Using (something similar to) a monad (Javascript promises do not form a monad) successfully is different than using the monad abstraction successfully. > and they are huge fans of do-notation in the from of async/await. Async / await is not monadic do-notation. Arguably, it has a somewhat similar relationship to the underlying promise abstraction that do-notation had to the monad abstraction, but they aren't the same thing. > Imperative programmers do not seem to have an issue with the idea of assignment, why are monads problematic Why are the two halves of this sentence connected to each other since they have no relationship other than the proximity they've been (bizarrely) placed in.
- jsjolen 7y ago
  Yeah, you're right that in some manners JS's promises do extend the semantics of a monad (notably in its impl. of return) but it is a monad though: function bindPromise(p, f) { return p.then(f); } function returnPromise(a) { return new Promise.resolve(a); } Proof of the laws left as an exercise to the reader :). But yes, you are correct that promises do quite a bit more than only being a monad, for example because of how they treat errors. EDIT: I concede, I am wrong! https://buzzdecafe.github.io/2018/04/10/no-promises-are-not-monads https://buzzdecafe.github.io/2018/04/10/no-promises-are-not-...
didibus 7y ago
Generally, I think people don't like Promises and async/await, since it is very goto like, but there's not a whole lot better currently. I also think there's nothing precluding some Monads to be good ideas and others to be bad ideas. Similarly, the delivery could have a big impact. So it might be the theory of it is good, but a better delivery in terms of programming UX needs to be used. So maybe the dot notation somehow delivers better then the do notation. Having said all that, I like Haskell, better than JS.
merb 7y ago
Promises are not monads. neither are scala's future.
- zzo38computer 7y ago
  I don't use Promises much, but Generators is like monads (but not monads on a category of pure functions, like it is in Haskell; also, these "monads" in JavaScript are not pure monads); actually, two kind of monads: return x; return x -> return yield*x return yield x; yield x -> yield*x (at least, I think it is; I may have made a mistake)

jowiar 7y ago

The big issue with Haskell isn’t the concepts — it’s the syntax. ASCII art as code is an abomination. Being unable to read code upon first glance it makes it inaccessible.

jes5199 7y ago

getting people who already agree with me to give me upvotes is the whole point of this website

AnimalMuppet 7y ago

> Imperative programmers do not seem to have an issue with the idea of assignment, why are monads problematic? This drive-by-question style makes it hard for me to know what your real point is. Are you saying that an assignment does the same thing as a monad? OK. That it is a monad? I doubt it; assignment doesn't have the right operators (you might argue that it does, but you'd have to really stretch it.) That it's just as simple and easy to understand as a monad? I call BS. > I have no idea what value your comment brings us except a way for people who already agree with you to give you upvotes, and what's the point in that? That kind of rhetoric is against the site guidelines.

dragonwriter 7y ago

> Javascript programmers seem to have no problem using a monad every day (promises) Using (something similar to) a monad (Javascript promises do not form a monad) successfully is different than using the monad abstraction successfully. > and they are huge fans of do-notation in the from of async/await. Async / await is not monadic do-notation. Arguably, it has a somewhat similar relationship to the underlying promise abstraction that do-notation had to the monad abstraction, but they aren't the same thing. > Imperative programmers do not seem to have an issue with the idea of assignment, why are monads problematic Why are the two halves of this sentence connected to each other since they have no relationship other than the proximity they've been (bizarrely) placed in.

jsjolen 7y ago
Yeah, you're right that in some manners JS's promises do extend the semantics of a monad (notably in its impl. of return) but it is a monad though: function bindPromise(p, f) { return p.then(f); } function returnPromise(a) { return new Promise.resolve(a); } Proof of the laws left as an exercise to the reader :). But yes, you are correct that promises do quite a bit more than only being a monad, for example because of how they treat errors. EDIT: I concede, I am wrong! https://buzzdecafe.github.io/2018/04/10/no-promises-are-not-monads https://buzzdecafe.github.io/2018/04/10/no-promises-are-not-...

didibus 7y ago

Generally, I think people don't like Promises and async/await, since it is very goto like, but there's not a whole lot better currently. I also think there's nothing precluding some Monads to be good ideas and others to be bad ideas. Similarly, the delivery could have a big impact. So it might be the theory of it is good, but a better delivery in terms of programming UX needs to be used. So maybe the dot notation somehow delivers better then the do notation. Having said all that, I like Haskell, better than JS.

merb 7y ago

Promises are not monads. neither are scala's future.

zzo38computer 7y ago
I don't use Promises much, but Generators is like monads (but not monads on a category of pure functions, like it is in Haskell; also, these "monads" in JavaScript are not pure monads); actually, two kind of monads: return x; return x -> return yield*x return yield x; yield x -> yield*x (at least, I think it is; I may have made a mistake)