Orthodox C++

What is Orthodox C++?

Orthodox C++ (sometimes referred as C+) is minimal subset of C++ that improves C, but avoids all unnecessary things from so called Modern C++. It's exactly opposite of what Modern C++ suppose to be.

Why not Modern C++?

Back in late 1990 we were also modern-at-the-time C++ hipsters, and we used latest features. We told everyone also they should use those features too. Over time we learned it's unnecesary to use some language features just because they are there, or features we used proved to be bad (like RTTI, exceptions, and streams), or it backfired by unnecessary code complexity. If you think this is nonsense, just wait few more years and you'll hate Modern C++ too ("Why I don't spend time with Modern C++ anymore" archived LinkedIn article).

Why use Orthodox C++?

Code base written with Orthodox C++ limitations will be easer to understand, simpler, and it will build with older compilers. Projects written in Orthodox C++ subset will be more acceptable by other C++ projects because subset used by Orthodox C++ is unlikely to violate adopter's C++ subset preferences.

Hello World in Orthodox C++

#include <stdio.h>

int main()
{
    printf("hello, world\n");
    return 0;
}

What should I use?

• C-like C++ is good start, if code doesn't require more complexity don't add unnecessary C++ complexities. In general case code should be readable to anyone who is familiar with C language.
• Don't do this, the end of "design rationale" in Orthodox C++ should be immedately after "Quite simple, and it is usable. EOF".
• Don't use exceptions.
• Don't use RTTI.
• Don't use C++ runtime wrapper for C runtime includes (<cstdio>, <cmath>, etc.), use C runtime instead (<stdio.h>, <math.h>, etc.)
• Don't use stream (<iostream>, <stringstream>, etc.), use printf style functions instead.
• Don't use anything from STL that allocates memory, unless you don't care about memory management.
• Don't use metaprogramming excessively for academic masturbation. Use it in moderation, only where necessary, and where it reduces code complexity.
• Wary of any features introduced in current standard C, ideally wait for improvements of those feature in next iteration of standard. Example constexpr from C11 became usable in C++14 (per Jason Turner cppbestpractices.com curator)

Is it safe to use any of Modern C++ features yet?

Due to lag of adoption of C++ standard by compilers, OS distributions, etc. it's usually not possible to start using new useful language features immediately. General guideline is: if current year is Cyear+5 then it's safe to start selectively using Cyear's features. For example, if standard is C11, and current year >= 2016 then it's probably safe. If standard required to compile your code is C17 and year is 2016 then obviously you're practicing "Resume Driven Development" methodology. If you're doing this for open source project, then you're not creating something others can use.

Any other similar ideas?

• Embedded C++
• Nominal C++
• Sane C++
• Why Your C++ Should Be Simple

Code examples

• Any C source that compiles with C++ compiler.
• DOOM 3 BFG
• Qt (when built with no-rtti, no-exceptions)
• dear imgui
• bgfx