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Comment by asdkjh345fd | Hacker News Reader

There is no such thing as imperative syntax. Syntax is completely orthogonal to being imperative, which is semantic not syntactic.

It isn't "almost C-like syntax", unless you define that to mean "if I do any amount of search and replace I can make it into valid C code that has completely different semantics". "x <- a" in haskell is not at all the same as "x = a" in C.

And that isn't the reason I said your comment is wrong. Your comment is wrong because do notation is not the result of "40 years of research in functional PL", nor is it an accomplishment. It is simple syntactic sugar that didn't come from research at all.

Your comment could be accurately summarized as "I would like to express how smug I feel for not learning something".

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> Your comment is wrong because do notation is not the result of "40 years of research in functional PL"

are you kidding me ? if a 2016 paper from Simon Peyton Jones isn't research then what is ? (https://dl.acm.org/doi/pdf/10.1145/3241625.2976007)

Have you considered reading it?

would you consider showing me a previous appearance of ApplicativeDo (not do notation of course, that shit is almost older than me) in scientific literature before that paper ? As surely, if a concept had existed for a long time it would be more relevant to start by the original paper that introduced it ?

Of course, the only thing 40 years of PL research resulted in was the do notation. I was under the impression that the do notation was syntax sugar for any kind of Monad - List, nondeterminism, asynchronous iO, parser combinations, exceptions etc. Stuff that appears as language features in other languages, but are just a library in Haskell.

But your chuckle has shown me that this code is just plain old C, with links to documents you haven't even read. Thank you for enlightening me, great chuckler.

I am honestly amazed at such an incredible bad reading of my comments. Next time I'll just write a phd chapter instead as apparently this is what is needed sometimes.

You are not capable of writing a PhD chapter. You lack the basic scientific thinking or method required. I suggest you focus on your core competency - chuckling.

Here is some basic reading material for you. Lets see if you can follow this

https://hackage.haskell.org/package/async-2.2.2/docs/Control...

   do a1 <- async (getURL url1)

      a2 <- async (getURL url2)

      page1 <- wait a1

      page2 <- wait a2

This implements async await in Haskell via a library using Monads. Hint: you cannot do this in C via any library. You need to modify the language. If you are uneducated about Monads, you might think this is similar to some kind of C code. It is not!

Here is the same do syntax being used to parse source files instead of doing async/await IO. Yes this parser will also perform backtracking etc, which will not be obvious to anyone who thinks this is some kind of transliteraton of C

https://markkarpov.com/tutorial/megaparsec.html

mySequence :: Parser (Char, Char, Char) mySequence = do

  a <- char 'a'

  b <- char 'b'

  c <- char 'c'

  return (a, b, c)

Hint: If you want to do something like this in C, you use yacc/bison, a parser generator tool - there is no library. And it is fucking ugly.

Hint 2: There are monads for parsing, async IO, exceptions, nondetermenism, monte carlo .........

Hint 3: The parser libraries are 25 years old.

Hint 4: Monad libraries represent less than 1% of PL research over the last 40 years.

Hint 5: C# LINQ is basically a Monad.

Hint 6: When confronted with something you don't understand, it is better to be quiet instead of opening your mouth and advertising your ignorance.

Hint 7: If your conversational style consists of chuckling and providing "Hints", be prepared for receiving a taste of the same medicine.

I am still humbled by your persistence in looking for deep truths in forum comments.

> This implements async await in Haskell via a library using Monads. Hint: you cannot do this in C via any library. You need to modify the language. If you are uneducated about Monads, you might think this is similar to some kind of C code. It is not!

it's still pretty much

> almost C-like syntax once again.

at no moment, not a single time, did I say in any way that I was talking about semantics but this is apparently a hill you wish to die on... so, by all means have fun !

Maybe you'll be more convinced by the exact text of the paper that introduced do-notation though ?

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.11....

let me quote it :

> Using monads gives functional programming an imperative flavour. Gofer supports a, so called, do notation which makes this imperative flavour more apparent.

or, let me rephrase that whole thing for you in a language that you seem to speak quite fluently:

    class BasicallyC m where
      (>>=)  :: m a -> (  a -> m b) -> m b
      (>>)   :: m a ->  m b         -> m b
      return ::   a                 -> m a
      fail   :: String -> m a

    class BasicallyC m => ImperativeFlavour m

You very conveniently skipped that you cant build async /await in C without modifying the language.

You also failed to show how parser combinator grammars such as yacc/bison/BNF forms are basically just imperative code.

Monads model effect systems; not imperative code.

I am impressed by your ability to argue about stuff you know nothing about, and linking to papers and documents you can't even read. Have you considered running for US president?

> You very conveniently skipped that you cant build async /await in C without modifying the language.

but async / await is semantics, not syntax, thus completely irrelevant to the conversation. you want an example of building async / await into the syntax of C as a library ? tada !

    void* async(...) { return NULL; }
    void await(void* ptr) { }

    int main(int argc, char** argv) { 
       void* handle = async(printf("foobar"));
       await(handle);
    }

or maybe you would prefer the more "modern" version, still compatible with pure C89 syntax though ?

    #define async
    #define await (void)

    int main(int argc, char** argv) { 
       auto x = async printf("foobar");

       /* wow, you can even compose it ! */
       auto y = async 2 * x;

       await x;
    }

please go on, this is super entertaining !

Wow man! your async-await code actually does nothing! I don't think I have argued so much and so far with an idiot!

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