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by brudgers 3249 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
1 comments
mhh__ 3248 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 3247 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__ 3247 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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