What language is Haskell written in?

Question

Also (besides the title question), is there source code available for different impure Haskell functions like IO?

I don't mean the Haskell side of the code, but whatever Haskell implements to do IO.

Answer 1

Haskell implementations are written in a range of languages.

For example, GHC is:

• runtime: a mixture of C, assembly and C--
• compiler: Haskell, Happy (for parsing), and Alex (for lexing)
• libraries: Haskell and a few C bindings, a little assembly and C--

The primops are the native instructions of the runtime. They in turn are implemented in the runtime via C, C-- and assembly fragments.

IO in particular is mediated via the IO manager, and via foreign libraries of IO primitives.