Re: what's the difference?
On Apr 19, 11:59 am, Pavel Minaev <int...@gmail.com> wrote:
On Apr 18, 3:44 pm, Andrey Bulat <andrey.bu...@gmail.com> wrote:
void func(MyClass *pMyClass)
void func(MyClass& MyClass)
What's the difference of two? The first pass the address of the
MyClass,
how about the 2nd one?
usually which one is preferred?
Main difference is in early binding of reference type MyClass& and
possible late binding of pointer MyClass*
If you plan to use virtual functions you should use pointer:
class MyClass{ virtual void f1(); }
class MyClass2: MyClass { virtual void f1(); }
void func(MyClass *pMyClass) { ... pMyClass->f1(); ....}
int main(){
MyClass* p = new MyClass2();
func(p);
This is absolutely wrong. With respect to virtual function binding,
references work in exact same way as pointers do, deferring it till
run-time.
{ clc++m banner removed; please do it yourself. -mod }
Ok,
I will change the sample:
int main()
{
MyClass obj;
MyClass2 obj1;
MyClass& objArray[2];
objArray[0] = obj;
objArray[1] = obj1;
for(int i=0; i<2; i++)
{
func2(objArray[i]);
}
}
This code produces errors connected with illegal use of array of
reference type.
So references and pointers are not the same (at least all pointers
have same sizeof).
You are right when you say that "With respect to virtual function
binding,
references work in exact same way as pointers do" but I am not sure
that in case of composites and/or collections design (most frequent
use case for using of virtual functions) you will use reference types.
About early/late binding - I didn't read about it with respect to
reference types(Can you give me reference?), but if we use single
object and reference to it it seems that it is possible to make
compile-time binding (I don't know how to check it).
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