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#ifndef MLIB__QMACROS_H
#define MLIB__QMACROS_H
/* Macros for qualifier-preserving functions. These are used to create wrappers
around some functions which will return a const-qualified pointer if the
input pointer is const-qualified, and a non-const-qualified pointer
otherwise.
The macros are taken from the N3020 proposal for C23. */
/* clang-format off */
#define _MLIB_PTR_IS_CONST(P) \
_Generic(1 ? (P) : (void *)(P), \
const void *: 1, \
default: 0)
#define _MLIB_STATIC_IF(P, T, E) \
_Generic(&(char[!!(P) + 1]){0}, \
char(*)[2]: T, \
char(*)[1]: E)
#define _MLIB_Q_PTR(T, F, S, ...) \
_MLIB_STATIC_IF(_MLIB_PTR_IS_CONST((S)), \
(const T *)(F)(__VA_ARGS__), \
(T *)(F)(__VA_ARGS__))
/* clang-format on */
#endif /* !MLIB__QMACROS_H */
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