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Are you speaking from experience? The article is about the author’s experience from a year of using Haskell. I don’t think it’s fair or constructive to disagre

Are you speaking from experience? The article is about the author’s experience from a year of using Haskell. I don’t think it’s fair or constructive to disagree with his findings unless you also have experience using the language, and it doesn’t sound like that is the case.

microtherion 7y ago
So if somebody asserted that INTERCAL-72 is the proper language to use for production code, you would consider it unfair to contradict them until you've used INTERCAL in production code yourself? Personally, I would not necessarily disbelieve somewhat propagating Haskell as a production ready language. However, I'm fairly confident that it would be thoroughly unsuited to any areas of work I regularly operate in. I have tried a number of times to learn Haskell (from a variety of tutorials and text books). I find myself nodding along sympathetically at the fundamentals (functional purity, non-strict evaluation). I can follow the initial chapters. And somewhere between "Functor" and "Applicative", I tend to lose the plot. Then I look at supposedly real world code like the URL shortener in Allen/Moronuki's "Haskell Programming from First Principles", and I just can't make heads or tails of it: https://github.com/bitemyapp/shawty-prime/blob/master/app/Main.hs https://github.com/bitemyapp/shawty-prime/blob/master/app/Ma... app :: R.Connection -> ScottyM () app rConn = do get "/" $ do uri <- param "uri" let parsedUri :: Maybe URI parsedUri = parseURI (TL.unpack uri) case parsedUri of Just _ -> do shawty <- liftIO shortyGen let shorty = BC.pack shawty uri' = encodeUtf8 (TL.toStrict uri) resp <- liftIO (saveURI rConn shorty uri') html (shortyCreated resp shawty) Nothing -> text (shortyAintUri uri) If that's supposed to be the way to write production code in the future, count me out!
- whateveracct 7y ago
  What exactly is wrong with it? I've never even used the Scotty library or monad being used and I can understand it.
  - microtherion 7y ago
    1. I have a vague idea what the second "do" is for. I don't have the slightest idea what the first "do" does. 2. I have some idea what "$" is, but I have no idea what it does in this context. 3. param "uri" is presumably extracting a parameter, presumably from the result of an incoming HTTP request. How is that request passed into "app"? How is it passed into the "get"? How is it passed to "param"? 4. Why does "parsedURI" need a type signature? 5. "Just/Nothing" more or less makes sense, but "Left/Right" (used outside the excerpt I quoted) is a notation that makes about as much sense to communicate meaning as "car/cdr" does in Lisp. 6. A response is generated. How does that response get back to the client? 7. What does liftIO do? 8. The overall syntax is just a pile of wrongness. There are left pointing arrows and right pointing arrows, which have completely different (and entirely non-symmetric) functions. There is an equals sign, which has a somewhat similar role to a left pointing arrow, but for some reason needs a completely different operator. There is a right pointing arrow in the function signature which is completely unrelated to the arrow in the case statement. There is an empty pair of parentheses doing Curry knows what. There are return values, which you can identify by following the peaks and valleys of the indentation. So, TL;DR, this is an incomprehensible control and data flow, wrapped in an ugly syntax.
    - whateveracct 7y ago
      Look, I sympathize with you because Haskell is not easy to learn by any means so I understand someone not liking it. If I get time later I'll go item-by-item and explain. There's a lot of questions there but it's actually just a few fundamental concepts. But I've seen engineers with only C/C++ experience get onboarded and write code with the same concepts & more complicated ones as the link shortener above. The key was onboarding by someone who knew Haskell well. Haskell companies need a culture of learning _and_ teaching to truly thrive and counteract downsides of the language like hiring pool and learning curve.
    - wolco 7y ago
      Could be a fun game. I'll guess. No haskell knowledge. PHP background. 1. Connect to remote connection. DO - wait.. 2. $ Loop-over 3. It comes from a config file with a hardcoded value and is globally included 4. Because it could be reused to handle a different types. 6. Text is printing to standard output. 7. Creating and Repointing the response to the resp var
- tome 7y ago
  This is roughly the same structure as the code you’d write in Python flask. There’s nothing unusual about it beyond Haskell’s syntax.
- mbrodersen 7y ago
  > If that's supposed to be the way to write production code in the future, count me out! Eh? Sorry but the code is really clear to me? Which parts do you find difficult to read?
- dragonwriter 7y ago
  The only thing I see bad about that code is some bad variable naming, especially shorty/shawty, and possibly a couple bits of needless and unhelpful verbosity. Neither are inherent to Haskell.

microtherion 7y ago

So if somebody asserted that INTERCAL-72 is the proper language to use for production code, you would consider it unfair to contradict them until you've used INTERCAL in production code yourself? Personally, I would not necessarily disbelieve somewhat propagating Haskell as a production ready language. However, I'm fairly confident that it would be thoroughly unsuited to any areas of work I regularly operate in. I have tried a number of times to learn Haskell (from a variety of tutorials and text books). I find myself nodding along sympathetically at the fundamentals (functional purity, non-strict evaluation). I can follow the initial chapters. And somewhere between "Functor" and "Applicative", I tend to lose the plot. Then I look at supposedly real world code like the URL shortener in Allen/Moronuki's "Haskell Programming from First Principles", and I just can't make heads or tails of it: https://github.com/bitemyapp/shawty-prime/blob/master/app/Main.hs https://github.com/bitemyapp/shawty-prime/blob/master/app/Ma... app :: R.Connection -> ScottyM () app rConn = do get "/" $ do uri <- param "uri" let parsedUri :: Maybe URI parsedUri = parseURI (TL.unpack uri) case parsedUri of Just _ -> do shawty <- liftIO shortyGen let shorty = BC.pack shawty uri' = encodeUtf8 (TL.toStrict uri) resp <- liftIO (saveURI rConn shorty uri') html (shortyCreated resp shawty) Nothing -> text (shortyAintUri uri) If that's supposed to be the way to write production code in the future, count me out!

whateveracct 7y ago
What exactly is wrong with it? I've never even used the Scotty library or monad being used and I can understand it.
- microtherion 7y ago
  1. I have a vague idea what the second "do" is for. I don't have the slightest idea what the first "do" does. 2. I have some idea what "$" is, but I have no idea what it does in this context. 3. param "uri" is presumably extracting a parameter, presumably from the result of an incoming HTTP request. How is that request passed into "app"? How is it passed into the "get"? How is it passed to "param"? 4. Why does "parsedURI" need a type signature? 5. "Just/Nothing" more or less makes sense, but "Left/Right" (used outside the excerpt I quoted) is a notation that makes about as much sense to communicate meaning as "car/cdr" does in Lisp. 6. A response is generated. How does that response get back to the client? 7. What does liftIO do? 8. The overall syntax is just a pile of wrongness. There are left pointing arrows and right pointing arrows, which have completely different (and entirely non-symmetric) functions. There is an equals sign, which has a somewhat similar role to a left pointing arrow, but for some reason needs a completely different operator. There is a right pointing arrow in the function signature which is completely unrelated to the arrow in the case statement. There is an empty pair of parentheses doing Curry knows what. There are return values, which you can identify by following the peaks and valleys of the indentation. So, TL;DR, this is an incomprehensible control and data flow, wrapped in an ugly syntax.
  - whateveracct 7y ago
    Look, I sympathize with you because Haskell is not easy to learn by any means so I understand someone not liking it. If I get time later I'll go item-by-item and explain. There's a lot of questions there but it's actually just a few fundamental concepts. But I've seen engineers with only C/C++ experience get onboarded and write code with the same concepts & more complicated ones as the link shortener above. The key was onboarding by someone who knew Haskell well. Haskell companies need a culture of learning _and_ teaching to truly thrive and counteract downsides of the language like hiring pool and learning curve.
  - wolco 7y ago
    Could be a fun game. I'll guess. No haskell knowledge. PHP background. 1. Connect to remote connection. DO - wait.. 2. $ Loop-over 3. It comes from a config file with a hardcoded value and is globally included 4. Because it could be reused to handle a different types. 6. Text is printing to standard output. 7. Creating and Repointing the response to the resp var
tome 7y ago
This is roughly the same structure as the code you’d write in Python flask. There’s nothing unusual about it beyond Haskell’s syntax.
mbrodersen 7y ago
> If that's supposed to be the way to write production code in the future, count me out! Eh? Sorry but the code is really clear to me? Which parts do you find difficult to read?
dragonwriter 7y ago
The only thing I see bad about that code is some bad variable naming, especially shorty/shawty, and possibly a couple bits of needless and unhelpful verbosity. Neither are inherent to Haskell.