GSL violates CppCoreGuidelines both ES.32 and ES.33:

[jmatzen]

GSL/include/gsl/gsl_assert

Line 170 in 1212bea

#define Expects(cond) GSL_CONTRACT_CHECK("Precondition", cond)

Naming violates both ES.32 and ES.33:

https://github.com/isocpp/CppCoreGuidelines/blob/master/CppCoreGuidelines.md#S-interfaces

"Scream when you see a lower case macro." While it's not entirely lower case, obvious violation is obvious.

[B1Z0N]

It is necessary, because it is another feature of GSL(see I.6 Expects and I.8 Ensures).

So it should stay named this way. We can change it to constexpr function, but two obstacles in our way:

1. Not all compilers supporting gsl also support constexpr(not sure about this, i am new to this library, likely it is true, is it?).
2. Why do we need to bother the compiler if we could just use bare macro and bother preprocessor? which seems to be a lot faster(not sure about this too, but i know that C++ compiler is slow, so preprocessor is likely to be faster, because it is more mindless, in a good way).

Yeah, i bet core guidelines have self-violations. It is a complex system, and self-violations are a property of complex systems.