5 ms·

I agree, auditing Haskell's performance characteristics is not easy. Then again, nothing in Haskell is easy.

by GhotiFish 14y ago

miga 14y ago
Writing short and clear code in Haskell is definitely easy. As for optimization - it quite often does it for you too!
- GhotiFish 14y ago
  !!! I have never met a single person who has said this, let alone capable of following through. If you are capable, I am envious of your determination/natural talent. Or alternatively I and every programmer I know are idiots. Actually both seem like possibilities.
  - nilkn 14y ago
    > Or alternatively I and every programmer I know are idiots. Most programmers haven't taken the time to actually learn Haskell. Haskell only seems hard at first because it incorporates a lot of ideas that other languages do not. For a lot of developers, learning Haskell is a little bit like learning to program from scratch all over again. In that sense, yes, I guess it's hard, but so was whatever language you learned first.
    - mbel 14y ago
      > For a lot of developers, learning Haskell is a little bit like learning to program from scratch all over again. I find this to be the greatest joy of learning a new paradigm, everything is new and unknown, so even simple things are fun (again).
    - miga 14y ago
      > Haskell only seems hard at first because it incorporates a lot of ideas that other languages do not. Indeed, even if you know Haskell, it may take years to master all classes in its standard library and most commonly used modules (like Parsec.)
  - swift 14y ago
    I have to agree with the GP here. Haskell is actually an exceptionally simple, easy language to work with, once you get the basic concepts down. I have occasionally suffered some confusion in Haskell because of poorly documented third-party libraries, but the language itself is a joy.
    - viraptor 14y ago
      I'd add a qualifier that if you know what you're writing and you're writing from scratch, it's relatively easy. Modifying existing programs can present an interesting challenge. For example once you have a working program and decide that actually some value could be read/written using a file instead of computed at runtime and the place you use it is 10 levels deep after calling a non-IO function, you've got two choices. Unsafe IO (then why not use it everywhere) or a minor program redesign. Haskell is the only language where I run into this kind of situation. (it's still quite simple despite this)
      - tome 14y ago
        If your program is well factored then it probably won't be hard to switch to IO ten levels deep. Bonus: Haskell makes refactoring easy!
        viraptor 14y ago
        Yes, but what happens to apps which depend on this piece of code? Suddenly the signatures change and you affect everyone with a change which should be completely transparent for them.
        tome 14y ago
        It's hard to discuss without an example.
      - mightybyte 14y ago
        I'd actually argue that modifying existing programs is where Haskell really shines. Strong static types and purity allow you to know a LOT more about arbitrary bits of code than any other language in mainstream use today.
  - ghc 14y ago
    Haskell has a difficult learning curve, that is all. A person coming to Vim from a modeless editor might feel the same way, but nobody doubts that someone familiar with Vim finds it easy to use. It took me a couple of years to "get" Haskell, but once you do it is very easy write clear, concise code with.
  - gtani 14y ago
    !!! I'm sure you're not an idiot. Have you tried the School of Haskell, it incorporates the minimum viable skills for learning haskell (pulling code apart in the REPL, and understanding type signatures, pattern matches and compiler type check errors) https://www.fpcomplete.com/school/how-to-use-the-school-of-haskell/learning-haskell-at-the-soh https://www.fpcomplete.com/school/how-to-use-the-school-of-h...
ufo 14y ago
While its true that lazy evaluation makes it harder to think about performance (specially memory use), the flipside is that it makes it easier to reason about programs at a higher level and you have more freedom when defining abstractions. For example, in Haskell you can freely rewrite common subexpression with a let whenever you want and in whatever order you want. --original (f x) ... (f x) --let let y = f x in y ... y On the other hand, if your language has side effects these sort of transformations are not always safe.
- plinkplonk 14y ago
  having side effects and having lazy evaluation are distinct features though. One can conceive of a strictly evaluated haskell-like which isolates side effects in monads and is still largely composed of pure functions.
  - tome 14y ago
    One can conceive of it, and yet it's never been done. Curious.
    - nilkn 14y ago
      There is Idris: http://idris-lang.org/ http://idris-lang.org/ It seems similar to what plinkplonk is talking about.
      - tome 14y ago
        Hmm, I always thought of Idris, Coq and Agda as proof assistants rather than programming languages, but perhaps that's just me being unimaginative.
        cyrus_ 14y ago
        Idris is explicitly billed as a programming language. You can do pretty sophisticated programming in Coq too (Coq can be reasonably straightforwardly compiled down to Ocaml, Haskell and some other languages.)

I agree, auditing Haskell's performance characteristics is not easy. Then again, nothing in Haskell is easy.

miga 14y ago

Writing short and clear code in Haskell is definitely easy. As for optimization - it quite often does it for you too!

GhotiFish 14y ago
!!! I have never met a single person who has said this, let alone capable of following through. If you are capable, I am envious of your determination/natural talent. Or alternatively I and every programmer I know are idiots. Actually both seem like possibilities.
- nilkn 14y ago
  > Or alternatively I and every programmer I know are idiots. Most programmers haven't taken the time to actually learn Haskell. Haskell only seems hard at first because it incorporates a lot of ideas that other languages do not. For a lot of developers, learning Haskell is a little bit like learning to program from scratch all over again. In that sense, yes, I guess it's hard, but so was whatever language you learned first.
  - mbel 14y ago
    > For a lot of developers, learning Haskell is a little bit like learning to program from scratch all over again. I find this to be the greatest joy of learning a new paradigm, everything is new and unknown, so even simple things are fun (again).
  - miga 14y ago
    > Haskell only seems hard at first because it incorporates a lot of ideas that other languages do not. Indeed, even if you know Haskell, it may take years to master all classes in its standard library and most commonly used modules (like Parsec.)
- swift 14y ago
  I have to agree with the GP here. Haskell is actually an exceptionally simple, easy language to work with, once you get the basic concepts down. I have occasionally suffered some confusion in Haskell because of poorly documented third-party libraries, but the language itself is a joy.
  - viraptor 14y ago
    I'd add a qualifier that if you know what you're writing and you're writing from scratch, it's relatively easy. Modifying existing programs can present an interesting challenge. For example once you have a working program and decide that actually some value could be read/written using a file instead of computed at runtime and the place you use it is 10 levels deep after calling a non-IO function, you've got two choices. Unsafe IO (then why not use it everywhere) or a minor program redesign. Haskell is the only language where I run into this kind of situation. (it's still quite simple despite this)
    - tome 14y ago
      If your program is well factored then it probably won't be hard to switch to IO ten levels deep. Bonus: Haskell makes refactoring easy!
      - viraptor 14y ago
        Yes, but what happens to apps which depend on this piece of code? Suddenly the signatures change and you affect everyone with a change which should be completely transparent for them.
        tome 14y ago
        It's hard to discuss without an example.
    - mightybyte 14y ago
      I'd actually argue that modifying existing programs is where Haskell really shines. Strong static types and purity allow you to know a LOT more about arbitrary bits of code than any other language in mainstream use today.
- ghc 14y ago
  Haskell has a difficult learning curve, that is all. A person coming to Vim from a modeless editor might feel the same way, but nobody doubts that someone familiar with Vim finds it easy to use. It took me a couple of years to "get" Haskell, but once you do it is very easy write clear, concise code with.
- gtani 14y ago
  !!! I'm sure you're not an idiot. Have you tried the School of Haskell, it incorporates the minimum viable skills for learning haskell (pulling code apart in the REPL, and understanding type signatures, pattern matches and compiler type check errors) https://www.fpcomplete.com/school/how-to-use-the-school-of-haskell/learning-haskell-at-the-soh https://www.fpcomplete.com/school/how-to-use-the-school-of-h...

ufo 14y ago

While its true that lazy evaluation makes it harder to think about performance (specially memory use), the flipside is that it makes it easier to reason about programs at a higher level and you have more freedom when defining abstractions. For example, in Haskell you can freely rewrite common subexpression with a let whenever you want and in whatever order you want. --original (f x) ... (f x) --let let y = f x in y ... y On the other hand, if your language has side effects these sort of transformations are not always safe.

plinkplonk 14y ago
having side effects and having lazy evaluation are distinct features though. One can conceive of a strictly evaluated haskell-like which isolates side effects in monads and is still largely composed of pure functions.
- tome 14y ago
  One can conceive of it, and yet it's never been done. Curious.
  - nilkn 14y ago
    There is Idris: http://idris-lang.org/ http://idris-lang.org/ It seems similar to what plinkplonk is talking about.
    - tome 14y ago
      Hmm, I always thought of Idris, Coq and Agda as proof assistants rather than programming languages, but perhaps that's just me being unimaginative.
      - cyrus_ 14y ago
        Idris is explicitly billed as a programming language. You can do pretty sophisticated programming in Coq too (Coq can be reasonably straightforwardly compiled down to Ocaml, Haskell and some other languages.)