2009/5/6 Rouan van Dalen
I know about Happy. Is that a good tool to use?
Alex and Happy are used in (at least) these two packages: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/language-python http://hackage.haskell.org/cgi-bin/hackage-scripts/package/language-c You should be able to find lots of useful code to start with in both of those. You can get good performance out of Alex and Happy. Of course there are more considerations than just performance, and you will get different opinions about those other aspects. I wrote the python parser above and I was quite pleased with Alex and Happy from a usability perspective. LLVM is a nice framework for building the backend of a compiler, and the Haskell bindings are quite useful: http://hackage.haskell.org/cgi-bin/hackage-scripts/package/llvm The amount of work you have to do depends on your runtime system (GC, threads, exceptions etc). If your language has fairly conventional semantics (a typical imperative language) then you can reuse a lot of the existing infrastructure that LLVM provides.
On another note, how is the operator + implemented in haskell?
It is good to differentiate Haskell "the language specification" from compilers (and other tools) which implement it. The language specification does not say exactly how the primitive operations should be implemented; that is a detail which is up to the compiler writer to decide. GHC's implementation is the best documented, and there are many research papers which describe aspects of it (some outdated). For numerical primitives, you could start by looking at this paper: "Unboxed values as first class citizens in a non-strict functional language" Peyton Jones and Launchbury. http://research.microsoft.com/en-us/um/people/simonpj/papers/unboxed-values.... Cheers, Bernie.