Comment by FwarkALark | Hacker News Reader

Comment by FwarkALark | Hacker News Reader

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> In this case, ‘stack-based language’ is used as a term of art.

This is a shitty and broken term. Hence my comment.

> is a language which there’s a stack threaded through successive procedure calls, where access to the values on that stack are accessed by popping them off and computing with them, then returning a result via a push.

You're just describing a procedural language that returns values. I suppose you could also describe a procedural language that doesn't return but what would be the point? You're just describing a form of indirect subroutines that revolve around jumps rather than the natural instruction progression. This has been a wildly unpopular method outside of entering a performance loop for many decades. It knows it will never have to exit/unwind the stack/call any kind of destructor or deallocation callback when entering a non-exiting loop.

Ok so why don't people (you!) just say "concatenative" given that other languages are trivially stack-based as well? How is it surprising at all that it's mostly syntax and a mediocre runtime (as the majority of languages can boast) that differentiates your pet language from other languages? Can we just admit that one of these options has a complex syntax and the other has a trivial syntax?

I’m not sure why my comment elicited such a volatile response, but assuming you are just using emphatic language for effect I will respond.

The main point you made that I can not agree with the characterization of other languages being ‘trivially stack-based’. Other languages in the Algol, ML, Lisp families have stacks that are an implementation detail of their function semantics. In those languages the stack is an implicit storage mechanism that merely holds values which are semantically associated with some ‘variable’ in the program syntax. In ‘stack-based languages’ the stack is, most usually, an explicit semantic construct which acts as the only available value for procedures to act on.

If your primary argument is against the term ‘stack-based’ that’s a personal position, but there are semantic differences between Forth and C, where emphasizing the explicitness of the stack in Forth is a viable point of divergence. As to using the term concatenative to describe a language, I have some opinions on that which fall outside the norm, so I tend to not use it to describe any of the ‘popular’ languages usually lumped under that umbrella.

I don’t know if the ‘pet language’ remark was towards me or in general, but it was certainly baseless if directed at my comment. If it is a general statement, I would only say that it is common for a community to settle on some terminology that they like and it’s rarely out-group pressure that forces a change in that language (see the ‘Alan Kay invented the term Object Oriented and it doesn’t describe C++’ argument that occurs frequently on forums like HN).

> In ‘stack-based languages’ the stack is, most usually, an explicit semantic construct which acts as the only available value for procedures to act on.

To the extent this is true, this is also true of all languages that anyone uses these days—C, JVM, Rust, Chez Scheme, GHC, python, ruby, ocaml, blah blah blah. The only difference is the syntax used to manipulate the stack. Acknowledging that syntax is the main difference from other languages seems key to evangelization. The idea of "implicit/explicit" doesn't really make sense. how do you refer to the stack in forth? You don't. How do you refer to the stack in C? You don't. Both operate with respect to the stack without ever referring to it via syntax. In both languages, the stack is invoked by referring to procedures/words.

Look if you want to keep up this fantasy that forth or factor is somehow more stack-oriented than any other languages, go right ahead. But you're going to fundamentally misunderstand why people use the language. It's the syntax! It was always about syntax. The stack is just a necessary implementation detail to deliver this syntax, same as in every other language that people actually use.

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