Re: proposal: stricter type-checking for macros

[Paul Jarc]

I wrote:
> #define TYPECHECK(x) (0? (void)(*(SCM*)0=(x)): (void)0)

BTW, does anyone know of a similar trick for arrays?  I can do this:

#define ARRAYCHECK(type, arr) \
  (0? (void)(*(type (**)[sizeof (arr)/sizeof (type)])0=&(arr)): (void)0)

But this requires the caller to know not just the element type of the
array, but also whether the array is const.  (Pointer to array of
const T is not compatible with pointer to array of non-const T.)  I'd
like to find a way to check that the expression is an array of const
or non-const T, giving a warning iff it is neither.  (That way,
ARRAYCHECK(char, "foo") would work with or without -Wwrite-strings.)


paul