Re: Returning Refs
EvilOldGit@googlemail.com wrote:
const Thing &operator++(int)
{
Thing temp = *this;
operator++();
return temp;
}
Is this code robust ?
Not only it's not robust, it has undefined behaviour if the caller
of this function tries to use the reference returned.
I get a compiler warning about returning a reference to a a local,
which I guess is because the compiler doesn't tell the difference
between this overload any any other function.
Huh?
Thing x,y;
x = y++;
Is OK because it's thrown away, and it's a copy of non-incremented y
that gets assigned.
Huh? No. It's not OK because by the time you try _using_ the return
value from the operator++(int) the local object has been destroyed
already.
y++ = x;
Does things to my head, but can't happen because I'm returning a
const.
Not sure what you mean by "can't happen". The compiler should
flag that as an error since you try assigning to a const object.
const_casting<> doesn't
Huh?
But could a (creatively stupid) user of my code do some harm ?
C++ is not fool-proof or malice-proof. Almost any program in C++
can be used in a way that would do some harm.
V
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