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by brudgers 3252 days ago
Every programming language can be described as "just a different syntax" for some other language, e.g. "C is just a different more Algol like syntax for assembly language." The differences in syntax is what can make a language useful (or not useful, e.g. Brainfuck).
2 comments
mhh__ 3252 days ago
That isn't really true.

There are clear differences in semantics between most programming languages. C is not just a different syntax over assembly: It has a type system, and obviously restricts what you can do (e.g. C abstracts over the registers)

A higher level language can be translated to a lower level one, (hence why Haskell can exist), but saying it's a purely syntactic transformation is extremely reductive.

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brudgers 3251 days ago
A Haskell program compiles to something that uses places and mutates what is stored in those places because a Haskell program ulitimately runs on a machine designed with the Von Neumann architecture.

Reduction is what compilers do. In the old days C was often compiled to assembly (at least the parts that were not in-line assembly) and the assembly was assembled and all of it got linked into an executable. Crenshaw's classic Let's Build a Compiler is a great way to see how it was done even if it is written using Pascal. http://www.stack.nl/~marcov/compiler.pdf

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mhh__ 3251 days ago
Umm, I know how compilers work.

C is compiled to still compiles to assembly, but usually (GCC) your compiler driver handles assembling, linking etc.

Haskell is translated to core (basically a simplification of a small subset of Haskell), then the STG(The abstract machine, spinless-tagless-Gmachine) then Cmm (Basically unsafe C) then LLVM.

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brudgers 3250 days ago
The turtle at the bottom of Haskell is machine code...mutable non functional machine code that is isomorphic with the Haskell source.
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mhh__ 3250 days ago
The machine code can still be basically functional. GHC doesn't use any mutable data unless you tell it to, it generates and then immediately collects garbage rather than reuse mutable memory.

You can have mutable data in Haskell, obviously.

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Ace17 3251 days ago
Garbage collection, RAII, dynamic typing, template metaprogramming, macros, type inference, exceptions ... are not "syntactic" features of programming languages. Those are semantic features, that happen to have a syntax.

Reducing programming languages to syntax+isTuringComplete is missing the forest for the trees.

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brudgers 3251 days ago
I agree because I think dismissing Coffee++ as just Python-like syntax also seems to ignore semantics. That was the gist of my remark.
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