Macros

1. Constrained template macros
2. Version macros
3. OUTCOME_CO_TRY(var, expr)

   Evaluate within a coroutine an expression which results in an understood type, assigning T to a decl called var if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

4. OUTCOME_CO_TRYV(expr)/OUTCOME_CO_TRY(expr)

   Evaluate from within a coroutine an expression which results in an understood type, continuing execution if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

5. OUTCOME_CO_TRYV2(spec, expr)

   Evaluate an expression which results in an understood type, continuing execution if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

6. OUTCOME_CO_TRYV2_FAILURE_LIKELY(spec, expr)

   Evaluate an expression which results in an understood type, continuing execution if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

7. OUTCOME_CO_TRYV_FAILURE_LIKELY(expr)/OUTCOME_CO_TRY_FAILURE_LIKELY(expr)

   Evaluate from within a coroutine an expression which results in an understood type, continuing execution if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

8. OUTCOME_CO_TRYX(expr)

   Evaluate from within a coroutine an expression which results in an understood type, emitting the T if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

9. OUTCOME_CO_TRYX_FAILURE_LIKELY(expr)

   Evaluate from within a coroutine an expression which results in an understood type, emitting the T if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

10. OUTCOME_CO_TRY_FAILURE_LIKELY(var, expr)

    Evaluate within a coroutine an expression which results in an understood type, assigning T to a decl called var if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

11. OUTCOME_DISABLE_EXECINFO

    If defined, disables the use of the <execinfo.h> header (or the win32 emulation).

12. OUTCOME_ENABLE_LEGACY_SUPPORT_FOR

    Enables backwards features and naming compatibility for earlier versions of Outcome.

13. OUTCOME_NODISCARD

    How to tell the compiler than the return value of a function should not be discarded without examining it.

14. OUTCOME_REQUIRES(...)

    A C++ 20 requires(...), if available.

15. OUTCOME_SYMBOL_VISIBLE

    How to mark throwable types as always having default ELF symbol visibility.

16. OUTCOME_THREAD_LOCAL

    How to mark variables as having thread local storage duration.

17. OUTCOME_THROW_EXCEPTION(expr)

    How to throw a C++ exception, or equivalent thereof.

18. OUTCOME_TRY(var, expr)

    Evaluate an expression which results in an understood type, assigning T to a decl called var if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

19. OUTCOME_TRYV(expr)/OUTCOME_TRY(expr)

    Evaluate an expression which results in an understood type, continuing execution if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

20. OUTCOME_TRYV2(spec, expr)

    Evaluate an expression which results in an understood type, continuing execution if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

21. OUTCOME_TRYV2_FAILURE_LIKELY(spec, expr)

    Evaluate an expression which results in an understood type, continuing execution if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

22. OUTCOME_TRYV_FAILURE_LIKELY(expr)/OUTCOME_TRY_FAILURE_LIKELY(expr)

    Evaluate an expression which results in an understood type, continuing execution if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

23. OUTCOME_TRYX(expr)

    Evaluate an expression which results in an understood type, emitting the T if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

24. OUTCOME_TRYX_FAILURE_LIKELY(expr)

    Evaluate an expression which results in an understood type, emitting the T if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

25. OUTCOME_TRY_FAILURE_LIKELY(var, expr)

    Evaluate an expression which results in an understood type, assigning T to a decl called var if successful, immediately returning try_operation_return_as(X) from the calling function if unsuccessful.

26. OUTCOME_USE_STD_IN_PLACE_TYPE

    How to implement in_place_type_t<T> and in_place_type<T>.

27. OUTCOME_USE_STD_IS_NOTHROW_SWAPPABLE

    How to implement is_nothrow_swappable<T>.