| Interesting points. I personally consider Nim's metaprogramming to be the best there is, although I must admit that I have not tried D's yet. Let me try to give you some reasons why I love Nim (I'll try to touch on all the points you've made about D) :) Nim includes templates (declarative metaprogramming), and macros (procedural metaprogramming). The latter gives you access to Nim's AST. Macros (and compile-time functions) are evaluated using Nim's VM. The VM supports the full language, with the exception of FFI, but you do get special compile-time functions for reading files and executing external processes at compile-time so it's already very powerful! Nim compiles to C/C++ so interfacing with C (and C++) could not get easier. Have not tried writing a macro for my editor which converts a C definition into Nim, sounds like a fun thing to implement. > As far as I know (correct me if I'm wrong!) there's no way to declare pure functions in Nim. This is something I do all the time in D! By pure I assume you mean "side-effect free"? If so there is: http://nim-lang.org/docs/manual.html#pragmas-nosideeffect-pr... > Nim has memory-safety only when using the GC while D has decoupled it from the allocation strategy. D's memory-safety is actually part of the type-system (as function annotations) and I absolutely love it! Going to need to look into that. Sounds awesome! In any case, you should definitely give Nim another chance. I can certainly say that I will do the same for D :)
Thank you for taking the time to write this up! |
I'm also glad to see Nim having purity, its incredibly hard to go back once you've tasted it!
The Emacs macros I mentioned aren't saved anywhere; the similarities in syntax between C and D makes it very straightforward to write dumb macros on-the-fly and forget them afterwards. For the most part D improves on C's syntax by fixing a lot of its shortcomings and the macros merely reflect that.
One example would be to convert "#define foo 1" into "foo = 1," to be put inside an enum declaration. Another would be to remove the DLL_EXPORT references (as D does not require them). The function definitions themselves barely change at all :)
One thing I'm also curious about are compilation times. My D program still compiles under 2-3 seconds even with recursive reflection of 100+ aggregate types, outputting meta-data and code for every single type and field (to handle serialization, generate on-screen editors, resolve dependency graphs and more). I haven't found any other systems language giving me this much power for this little compilation times.
This even includes transforming my regex expressions into D code during compilation so the regexes get the full power of the language's optimizer.
I'll definitely keep Nim in mind for my next pet project, right now I'm getting over 30k LoCs in my D project and really don't want to switch languages halfway through! :)