include/nullable.h


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#ifndef AMAL_NULLABLE_H
#define AMAL_NULLABLE_H

struct __nullable_type_dummy{ int _; };

int assert_not_null(void *val);

#ifdef DEBUG
#define DefineNullablePtrType(type)                 \
    typedef struct type##_nullable type##_nullable; \
    struct type##_nullable {                        \
        type *value;                                \
    }
#define NullablePtr(type) type##_nullable
#define nullable_unwrap(nullable_type) \
    (assert_not_null((nullable_type).value) ? ((nullable_type).value) : NULL)
#define nullable_assign(nullable_type, new_value) ((nullable_type).value = (new_value))
#define is_not_null(nullable_type) ((nullable_type).value != NULL)
#define nullable_raw(nullable_type) ((nullable_type).value)
#else
#define DefineNullablePtrType(type)
#define NullablePtr(type) type*
#define nullable_unwrap(value) value
#define nullable_assign(nullable_type, new_value) ((nullable_type) = (new_value))
#define is_not_null(nullable_type) ((nullable_type) != NULL)
#define nullable_raw(nullable_type) (nullable_type)
#endif

#endif