Re: Reference to void
Lucian Radu Teodorescu wrote:
{ 8.3.2/1 prohibits declarations of references to void. -mod }
Hello
Is the following code valid?
int i = 5;
void* pv = &i;
void& rv = *pv; // Error here on VC 2005
If not, why isn't it valid?
For the same reason it is not legal to declare a variable with a void
type or to dereference a void pointer - "void" in C and C++ denotes
either that the type is not known (as in the case of a void pointer) or
there is no type at all (as in the case of a function returning void).
So whether the type that a void declaration represents is unknown or
absent, it should be clear that allocating, assigning or evaluating a
"void" type (or a reference to one) would either have unpredictable
consequences or not even be possible in the first place. In other
words: since a C++ program could not do anything useful with a
reference to void, the C++ language is better off without such a
concept.
Greg
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