CI:

Reference API docs: https://ned14.github.io/wg14_result/

Can be configured to be a standard library implementation for your standard C library runtime. Licensed permissively.

This is a 100% C reimplementation of https://ned14.github.io/outcome/experimental/, created as Outcome.Experimental is now on the WG14 C standardisation track and I no longer participate on WG21 (C++ standards). Features:

100% ABI compatible with the C++ implementation, you can freely switch between each, even by casting pointers on objects or having C++ call via virtual function into a C implementation, or vice versa.
Unlike the C API which C++ Outcome has shipped for years, this one does not require any C++ runtime to be linked into any final binaries.
Can be configured as a header-only library (unity build) which has headers also include their source files. If so:
- The usual C 90 minimum requirement for the headers is raised to C 11, as the library source code needs minimum C 11.
- If a C++ compiler is being used, the minimum requirement for the headers is raised to C++ 20 as previous C++ standards don't implement enough of C 11.

Example of use

todo

Supported targets

This library should work well on any POSIX implementation, as well as Microsoft Windows. You will need a minimum of C 11 in your toolchain to compile the library, however its header files work in all standards of C right back to C 90 (NOTE that some macros do use features from later C standards, if on an earlier C then don't use that macro).

Current CI test targets:

Ubuntu Linux, x64.
Mac OS, AArch64.
Microsoft Windows, x64.
ESP32, RISC V.

Current compilers:

GCC
clang
MSVC

Configuration

You can find a number of user definable macros to override in config.h. They have sensible defaults on the major platforms and toolchains.

Features from C++ <tt>status-code</tt> out of scope for the C implementation

status_code_errored, without Contracts it doesn't really make sense.
status_code mixins, which require template trait based inheritance to be easy to use.
quick_status_code_from_enum would need C compiler magic to work I think. Not ruling that out at all, but it's definitely a later proposal paper.
system_code_from_exception makes no sense without C++ exceptions.
C++ i/o stream support obviously makes no sense in C.

Performance

On my Threadripper 5975WX which is a 3.6Ghz processor bursting to 4.5Ghz on Linux:

todo

On a MacBook Pro M3 running ARM64

todo

On a MacBook Pro M3 running ARM64 Windows within a VM

todo

Todo

Ought to generate some sort of reference docs
Ought to generate examples to ensure optimised codegen
Convenience functions for serialising and printing.
Need example bindings for:
- Rust
- FORTRAN
- Swift

Features reimplemented in C from C++ <tt>status-code</tt>

[x] status_code_domain
[x] status_code<void> as status_code_untyped
[x] status_code_generic
[x] status_code(T)
[x] status_code_posix
[x] status_code_system
[x] result(T)
[x] TRY macros

After next WG14 meeting review

[ ] status_code_nested
[ ] status_code_getaddrinfo
[ ] status_code_http
[ ] status_code_win32
[ ] status_code_nt
[ ] status_code_com

Maybe in the future

[ ] status_code_cxx_error_code
[ ] status_code_boost_error_code