• AJG (7/7) Aug 17 2005 Hi,
• Jarrett Billingsley (4/9) Aug 17 2005 Why wouldn't it be? Casting to a void* is safe, since you can't read or...
• AJG (5/14) Aug 17 2005 What if it's a short, or a class, or something else other than an actual
• Ben Hinkle (9/24) Aug 17 2005 Check that the TypeInfo of the parameter subclasses TypeInfo_Pointer. Th...

AJG <AJG_member pathlink.com> writes:

Hi,

How can I test to see if a variadic parameter is null?

I don't think something like:

if (va_arg!(void*)(_argptr) == null) printf("Null");

Is safe.

Thanks,
--AJG.

"Jarrett Billingsley" <kb3ctd2 yahoo.com> writes:

"AJG" <AJG_member pathlink.com> wrote in message 
news:de0p3i$q1p$1 digitaldaemon.com...
 Hi,

 How can I test to see if a variadic parameter is null?

 I don't think something like:

 if (va_arg!(void*)(_argptr) == null) printf("Null");

 Is safe.

Why wouldn't it be?  Casting to a void* is safe, since you can't read or 
write it. 

AJG <AJG_member pathlink.com> writes:

Hi,

 How can I test to see if a variadic parameter is null?

 I don't think something like:

 if (va_arg!(void*)(_argptr) == null) printf("Null");

 Is safe.

Why wouldn't it be?  Casting to a void* is safe, since you can't read or 
write it. 

What if it's a short, or a class, or something else other than an actual
pointer, would it still work?

Thanks,
--AJG.

"Ben Hinkle" <ben.hinkle gmail.com> writes:

"AJG" <AJG_member pathlink.com> wrote in message 
news:de0sv9$sj3$1 digitaldaemon.com...
 Hi,

 How can I test to see if a variadic parameter is null?

 I don't think something like:

 if (va_arg!(void*)(_argptr) == null) printf("Null");

 Is safe.

Why wouldn't it be?  Casting to a void* is safe, since you can't read or
write it.

 What if it's a short, or a class, or something else other than an actual
 pointer, would it still work?

 Thanks,
 --AJG.

Check that the TypeInfo of the parameter subclasses TypeInfo_Pointer. That 
way you'll know the parameter isn't actually a short or a class reference. 
TypeInfo_Pointer is defined in object.d which is automatically imported so 
it is always available.

Note I haven't actually tried this - I just assume the typeid of a pointer 
subclasses TypeInfo_Pointer otherwise why have something called 
TypeInfo_Pointer :-P