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Comment by rbehrends | Hacker News Reader

> Every difference between Turing complete languages is a "syntax only thing".

I'm pretty sure you can't ignore language semantics here.

> You can certainly reimplement it on most functional languages with a syntax that is only a bit more verbose and error prone. That's not a win.

Note that I was giving examples from imperative languages; Haskell has the additional problem that it has to transform the do notation into what's essentially function composition; but function composition is already the natural denotational semantics of imperative code [1].

[1] https://en.wikipedia.org/wiki/Denotational_semantics#Denotat...

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> I'm pretty sure you can't ignore language semantics here.

As long as the languages operate on the same virtual computer (same IO capacities), you can create the same semantics on any language. At the worst case, you can write an interpreter for any language on any other language.

> but function composition is already the natural denotational semantics of imperative code

Most high-level languages got some influence by Lisp-style functional programing, so they transform into function reduction/composition with some amount of naturality. The imperative languages are the ones with the less straight-forward transformation, while Lisp is basically alone at the other extreme.

Pure function reduction/composition is a great representation for computer. It's simple to analyze, and cheap to represent. But I don't think it is that great for human consumption. Do notation is a bit more complex to represent, but often a lot more legible.

> As long as the languages operate on the same virtual computer (same IO capacities), you can create the same semantics on any language. At the worst case, you can write an interpreter for any language on any other language.

This is fairly tautological and would make semantics meaningless. I'm not talking about the universality of Turing-complete languages, but about the semantics of language constructs.

> Most high-level languages got some influence by Lisp-style functional programing, so they transform into function reduction/composition with some amount of naturality. The imperative languages are the ones with the less straight-forward transformation, while Lisp is basically alone at the other extreme.

This has nothing to do with what I said, so I'm not sure what your point is?

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