Comment by bmitc | Hacker News Reader

Comment by bmitc | Hacker News Reader

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I think the major thing is that F# did not ignore the things that came before it, whereas Python did. While Python did come about in the early 90s, it had already ignored things like Lisp, Scheme, Smalltalk, Erlang, and Standard ML (SML). As it evolved into the 2000s and 2010s, it continued to ignore developments. Compare that to Clojure, Elixir, and F#, and there's a stark difference. All three of those languages were designed to be highly pragmatic and not academic, but they all three stood on the shoulders before them. If you read interviews with van Rossum, he shows a complete unwillingness to accept the functional programming paradigm as pragmatically useful and basically rejects it wholesale. In his Slashdot interview, he explicitly said "functools (which is a dumping ground for stuff I don't really care about :-)".

https://developers.slashdot.org/story/13/08/25/2115204/inter...

It's frustrating to me, because if Python had adopted at least some of the things that languages like SML then OCaml and then F# were doing, it would dramatically elevate it. At the time of the interview, in which he goes on to state "Admittedly I don't know much about the field besides Haskell", the year was 2013, and so at that point, F#, Clojure, OCaml had already been around for a while, Erlang had been released with a permissive license, and Elixir had actually been released the year before. Further, it's not like even before that that Haskell was the only functional language. SML, Scheme, and even Racket (then known as PLT Scheme) had been around for a while.

Python is a wolf in sheep's clothing to me. It has a deceptively simple look at at the surface, but it is actually a quite complicated language when you get into it. I've done concurrent programming my entire programming life in F#, Elixir, and LabVIEW. I simply do not understand how to do concurrency things in Python in a reliable and composable way (for one, there's several different implementations of "concurrent" programming in Python with various impedance mismatches and incompatibilities). I.e., it's complicated.

There wasnt much before Python either, I know some people who think OS/2 was better for multi tasking than windows, but the popular market didnt seem to think so.

> (for one, there's several different implementations of "concurrent" programming in Python with various impedance mismatches and incompatibilities). I.e., it's complicated.

Is this because Python doesnt offer any Co-operative threading model and just exposes programmers to preemptive threading and all the different synchronisation facilities an OS provides? https://docs.microsoft.com/en-us/windows/win32/sync/synchron...

I dont have a problem with any of the synch objects because they also have strengths and weakness which are relevant to what ever the code is doing. Speed of synch objects is one factor, but there are others, like handling of shared data between two or more apps.

So are you saying F# removes the ability to choose synch objects?

Half the problem I find is just keeping up with different terminology used in various parts of the world.

huh. Forgot to mention tail recursion.

Isnt this a CPU optimisation thing, ie code & languages working better for some instruction sets than others?

One of the languages I've used in the past always performed best on certain AMD cpu's, but that was when we could choose what cpu the compiler was to optimise for, ie 286, 386 etc etc.

I'm also aware of backroom shenanigans going on with some languages and tools working better for some CPU's.

This 12 year old post goes into a lot of detail https://stackoverflow.com/questions/1414911/intel-x86-assemb...

Tail call optimization has nothing to do with optimizing for different CPUs, it's about dropping a function's stack frame when it's evaluating its return expression and its stack frame isn't needed anymore.

Is this the difference in calling conventions ie callee or caller stack clear up? https://en.wikipedia.org/wiki/X86_calling_conventions#List_o...

This is half the problem different terminology in use between different age groups, just like slang is different between different age groups.

I'm not sure, so here are a couple examples.

    def f() =
       g()

In a language implementation that doesn't optimize tail calls, the stack would look like the following after the call to g:

    g
    f
    main

In a language implementation that does optimize tail calls, the stack would look like this, because the result of f is whatever the result of g is so f is no longer needed:

    g
    main

If a language implementation doesn't optimize recursive tail calls, the following code will quickly overflow the stack and the program will crash:

    def loop() =
        do something...
        loop()

In a language implementation that does optimize recursive tail calls, this code can run forever because loop's stack frame gets replaced with the stack frame of the new call to loop.

The reason people want recursive tail calls optimized out is at a much higher level than anything to do with the actual CPU instructions being used, they just want to have a way to write recursive functions without worrying about the stack overflowing.

What's my age group, by the way?

I have never seen this referred to anything other than things like tail-call recursion, tail-call optimization, etc.

Languages like Python make implementing simple loops like:

    def loop():
        <whatever>
        loop()

impossible.

Python will reach a maximum recursion depth and error.

Why is this important? Like I said, it makes looping very easy. For example, actors can almost be trivially implementing in languages with tail-call recursion.

It’s not in Python because like most things in Python, van Rossum doesn’t like it because <reasons>.

https://stackoverflow.com/questions/13591970/does-python-opt...

There’s little point in having full traces of the data doing in and out of the tail-call loop is immutable, so you only really care about the current call of the function.

<goes away to find out what if its in my preferred language & tool>

Its not something I've every heard of before, I guess its peculiar to Python though but dont most languages have some eccentricity?

It's absolutely not peculiar to Python, it's something that every single language implementation has to make a decision on one way or the other.

Here's an SO answer from 2008 about how to enable TCO in various C and C++ compilers: https://stackoverflow.com/questions/34125/which-if-any-c-com...

There are many things both you and I have never heard of before. That's normal.

Yes, the different terminology is a reflection of the entrance of so many new entrants going for what is easy in the short term, instead of learning the theory of their industry and thus learning better approaches that are not 'immediately' obvious.

This lack of learning theory in our industry, instead going for something that is 'easy to get started' explains the popularity of python and javascript, and at the same time why python and javascript are littered with problems that have already been solved, and cluttering up the field of knowledge by reinventing terminology because they never learned the original existing terms.

Yea! And that's a big one.

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