Top D Features I Miss In C++

Published 2012-08-25 22:35 by Abscissa in Coding

I've spent the last month or so on a project that, due to factors beyond my control, must be in C++ and not D.

A little of my background first: I used C/C++ as my primary language in the late 90's and early 2000's. Liked it at the time, but then got fed up certain aspects and went looking for alternatives. Long story short, I found D, fell in love with it, and have been using it extensively for years.

Now that I'm back in C++-land (hey, it beats the hell out of writing a whole game entirely in a dynamic service/server-compiled toy from the same jokers folks who brought us the wonderful Flash), I've built up a list of the top things I miss from D when using C++. There's plenty of other great stuff in D that I miss, but these are the ones...so far...that are proving to be the most painful to live without in the particular project I'm working on (An iOS/Android puzzle-ish game). Other projects would likely have very different lists, of course.

Incidentally, this also serves as a deeper explanation for anyone who didn't understand the vague heckling of C++ in my previous post.

Top D Features I Miss In C++

1. Proper module system: One of the main things that drove me away from C++ in the first place. The header-file/text-inclusion hack is a colossal, anachronistic pain in the ass. There are so many problems with this one issue alone, I'm not sure they're even worth listing. But I will anyway because they deserve public ridicule:

   C++'s "Module" System Sucks

   • #ifndef _FILENAME_H_: All the reason you need to know C++'s module system sucks. Retarded hack.

   • Identifiers prefixed with psuedo-module vomit: Let's see... CIwFVec4... CIwGameActorImage... WTF? Can I haz FVec4 and ActorImage, plz? Yea, I know there's namespaces, but not everyone seems to use them. Somehow I have a feeling there's a good reason for that - besides just easier interfacing with D.

   • DRY? What's DRY? Derp derp durrr....

   • Scrambled modules! Let's chop up our module and play "What goes where?!?" Implementation files: non-inlined function bodies, non-member variables (which aren't evil globals in a language with proper modules), and private preprocessor directives. Header files: member variables, inlineable function bodies, public preprocessor directives, member accessibility (public/private), non-DRY duplication of non-inlined function signatures, plus includes and forward declarations that should be private but must be leaked out due to something else in the header needing to use them. Whee!

   • Header files are interface documentation? LIES! Seriously, look at your header files. You're really going to try to tell me that only contains the public interface? Then what's that private: section doing in there? And that forward declaration for an external class? If you want automatic documentation, run a damn documentation generator. They exist.

   • Headers affected by whatever headers were included before it: Hygiene? What's hygiene? And why is this compiling so slow? Durrr...I wonder why?

   • Fuck precompiled headers: Talk about "solving the wrong problem".

   • No RDMD (automatic dependency finding): Every...fucking...source file must be manually specified. I remember to do this about half the time.

   • And the #1 reason C++'s "module" system sucks: What is this, 1970?

2. Actual properties:

   foo->setX(foo->getX() + 1); // Suck my nutsack, C++

3. Metaprogramming that doesn't involve a text preprocessor or gobs of excessive template instantiations.

4. Sane type-name syntax: In C++, how do you spell int*[]* delegate()[]* (Ie, a pointer to an array of delegates which take no params and return a pointer to an array of int pointers)? Wrong! The correct answer is "Fuck you, I'm not attempting that shit in C++!"

5. Type deduction: Unfortunately, Marmalade doesn't yet support C++11, so I don't even get auto.

6. Closures, lambdas, nested functions: There's a good reason Qt in C++ requires a special preprocessor. (Yea, I'll care about C++11's features when I can rely on them actually existing in my compiler.)

7. No forward declarations: Was I wrong before? Maybe this is still 1970?

8. Actual reference types: And no, I don't mean Foo&.

9. Non-schizo virtual: C++'s member funcs are non-virtual by default...except the ones that are virtual by default and can't be sealed as final. WTF? WTF indeed. (Yes, I do understand how it works, but it works stupidly.)

10. Default initialization: Granted, I'd rather be told at compile-time about possibly using non-inited vars (ie, C#-style)...But garbage-initialization? Screw that. Especially for pointers, I mean, fuck, really?! Pain in the damn ass.

11. Fast compilation: Hooray for the world's slowest-compiling language! Whee!!

12. Polysemous literals: C++ can barely figure out that 2 can be a float. Gotta babysit it with 2.0f. Great.

13. Ranges: Fuck iterator pairs.

14. Named immutables/constants that actually exist in the real code, not just the preprocessor.

15. Designed by someone who actually fucking understands proper engineering.

Things I'm surprised I don't miss yet (but may still miss later and would undoubtedly miss if my project were for a different domain or maybe even just using different engine):

• Slices and string/array manipulation: Fuck null-terminated strings, fuck pointer/length pairs, and fuck everything in string.h.

• Associative arrays: Just works. Any key type. No syntactic bullshit.

• Scope guards: Also known as "RAII that isn't a contrived syntactical kludge".

• GC: You can pry manual memory management from my cold dead hands, but that doesn't mean I always wanna fuck with it.

• Foreach: I'm still convinced foreach(i; 0..blah) is essential for any modern language, but my prior experience with C/C++ seems to have left for(int i=0; i<blah; i++) irreparably burned into my brain.

And ok, to be perfectly fair to C++, let's turn things around a bit...

Things from C++ I miss when I go back to D:

• .......
• Ummm.....
• Not a fucking thing.

UPDATE (2012-09-12): Added "RDMD" to reasons C++'s module system sucks. Can't believe I forgot that before, that's a big one.