Николай Кудасов wrote:
Problem becomes much more complex when I want to add function calls into my language. Type class CallArgs has an instance CallArgs (IO a) (CodeGenFunction r (Value a)), which can't be given as a constraint in typed AST because of free variable r. For a long time I have had no idea of how I can add function calls into my language.
RankNTypes? First I was also annoyed by this 'r' type parameter. But I think it is there in order to assert that LLVM code blocks have the same return type in 'ret' instructions when composing them.
The only solution I see at the moment is to reject high-level llvm interface provided by llvm library and use directly FFI bindings to C.
I have not tried, but I would also think that the strongly typed llvm binding makes writing a compiler hard. However I enjoy it for just-in-time compilation and building an embedded domain specific language. For writing a compiler you might prefer the LLVM bindings that are created by David Terei for GHC's LLVM backend. PS: Also posted to haskell-llvm mailing list.