Consider the following code:
#include
typedef int t;
t a=42;
int main()
{
a.t::~t();
std::cout << a; //42
}
<
But it is not true, why?
§5.2.4/1:
The only effect is the evaluation of the postfix-expression before the dot or arrow.
Where the postfix-expression is the expression of the object for which the call takes place. Thus a pseudo destructor call, as a call to a trivial destructor, does not end the lifetime of the object it is applied to. For instance,
int i = 0;
(i += 5).~decltype(i)();
std::cout << i;
You can't actually call a destructor for scalars, because they don't have one (see [class.dtor]). The statement is solely allowed for template code in which you call the destructor of an object whose type you don't know - it removes the necessity of writing a specialization for scalar types.
It was noted in the comments that [expr.pseudo] does imply the existence of a destructor for scalars by
The use of a pseudo-destructor-name after a dot
.
or arrow->
operator represents the destructor for the non-class type named by type-name.
However, this is inconsistent with other parts of the standard, e.g. §12, which calls a destructor a special member function and mentions that
A destructor is used to destroy objects of its class type.
It appears to be an imprecision created in C++98 days.