The refreshing part about Haskell to me is that it is declarative. It feels more natural to describe what you want to happen than to try to think like a machine and compose sequential machine instructions for it each of which can fail at any execution.
Haskell's compiler is incredibly strict. It'll guide you until the code is near bullet proof. The outcome is that the surface area where things can go wrong is relatively a lot smaller than in just about any other language our there.
Haskell is not declarative. It is a specific form of lazy + graph-reductive. Thinking of it as declarative leads to polynomial exponential runtime cost in CPU/memory and not understanding why or how to fix it.
https://stackoverflow.com/questions/40130014/why-is-haskell-...
I'm not talking about the compiler or the evaluation. From programmer's perspective the language does seem fairly declarative to me, mostly consisting of expressions instead of statements.
I don't know what's wrong about thinking about expressions as declarative which in my opinion they are. How would thinking about expressions imperatively help me avoid those exponential runtime costs?
For example consider the list comprehension: [toUpper c | c <- s]
If you compare this with your typical imperative for loop to construct the same data structure I find this declarative.
Re:Haskell Fan Site
by pteredactyl on Sunday June 23, 2019 @11:23PM
(#20260226)
Thanks. You in the Bay by chance?
Re:Haskell Fan Site
by hardwaresofton on Monday June 24, 2019 @01:08AM
(#20260700)
Sorry super late but no, I'm in Tokyo actually (was in Austin before that) --feel free to reach out (email in bio) if you ever want to chat though!
> In my experience I've found real-world applications, by definition are never as pure and perfect as we like them to be. Users do stupid things, or vendor APIs don't quite fit what we want.
This is actually one of haskell's greatest strengths IMO -- it enforces the kind of discipline that sidesteps this problem completely. The kind of functions you write with haskell don't allow bullshit -- non-nullable types are the biggest example of this I can think of, there's also the pervasive use of `Maybe Value` and `Either SomeError Value` types.
In other places it's usually referred to as Domain Driven Design or the onion architecture -- but best practices for software development usually dictate that you get rid of bullshit as early as possible on the borders of your application. Put simply, don't let invalid/incorrect input make it into your system.
> And personally it's why I think the Haskellers I know often get stuck in the mud. Seems the language, or just the Haskellers I know, are better suited for a academic applications.
Totally true, we do get stuck in the mud, but it's such nice mud -- the things you worry about are just different (and I think this is what you're seeing). Roughly zero haskellers are worrying about NPEs -- there's no urge to get something to "just work" because "better" is right there, and haskell encourages you to strive for it.
That said, it's absolutely the case that a ton of energy in haskell land is spent on academic pursuits, but that's actually good imo, languages that don't do this get stale.
> I'd love to be proven wrong as I'm into type safety and FP, in general.
Well I don't know that this is something someone else can prove to you, outside of people just writing more middling/regular software in haskell and getting it out there, which is a bit of a community thing. I do my best to write practical haskell software and write about it, but a bunch of my projects aren't open source (just yet -- I'm heavily considering making one of them open source right now). Rust is also proving to be a huge (welcome) distraction because it gives much of the haskell creature comforts with within-C++/C range efficiency.
Maybe take haskell for a spin? The learning curve is high but it will bend your mind in a good way. Or if you're of the web persuasion, try Elm/Purescript, they're thoroughly practical.