Re: newbie on pointers
* Henrietta Denoue:
Hi,
What happens to a global pointer that is to be used in various
other objects, is instantiated in one object, then this second
object is deleted ? Is the pointer still valid ? like pseudo-code
---------------------------
// my global pointer, not a member of Classes A or B
X *x;
class A{
....
x = new X();
... do something with x
}
Class B {
...
do something with x;
}
int main()
{
A a;
B b;
a = new A();
....
delete a;
---------------
My question is : Is x still valid in B evenif A is deleted ?
Technically yes.
But don't do that. It's like consolidating the firm's bank accounts
into one big account completely accessible to every employee, with no
tracing of who has done what. Imagine how long that firm would last.
If instances of A and B need to communicate or share things then first
consider function arguments. Then there is a host of different
techniques that can be used for the cases where function arguments don't
cut it. If or when you find that a global (single, common, shared,
completely open bank account) is the only possible solution to the
requirements, then it's time to start questioning the requirements.
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