q: Pointer vs Reference question

[laniik]

Hi. If i have

Class Object {
}

void foo(Object* o)
{
}

void bar(Object& o)
{
}

int main()
{
Object o;
foo(&o);
bar(o);
return 0;
}

I know that in foo, the contents of o are not copied as main just
passes a pointer to the function foo, but my question is, in bar, is
the object o copied? or is just a reference to it passed to the
function? thanks!

Oliver

[Alf P. Steinbach]

* laniik:

Class Object {
}
NP: missing semicolon.

void foo(Object* o) {}
void bar(Object& o) {}

int main()
{
Object o;
foo(&o);
bar(o);
return 0;
}

I know that in foo, the contents of o are not copied as main just
passes a pointer to the function foo, but my question is, in bar, is
the object o copied? or is just a reference to it passed to the
function? thanks!

Just a reference, no object copying.

--
A: Because it messes up the order in which people normally read text.
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A: Top-posting.
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[laniik]

thanks!

what a great sig also

[Peter Julian]

"laniik" <la****@yahoo.com> wrote in message
news:11**********************@g43g2000cwa.googlegr oups.com...

Hi. If i have

Class Object {
}

void foo(Object* o)
{
}

void bar(Object& o)
{
}

int main()
{
Object o;
foo(&o);
bar(o);
return 0;
}

I know that in foo, the contents of o are not copied as main just
passes a pointer to the function foo, but my question is, in bar, is
the object o copied? or is just a reference to it passed to the
function? thanks!

The function bar(...) doesn't use a copy either. But there is more happening
here than meets the eye.

The Object& o parameter in bar(...) can't be unbound, not true for a
pointer. This does not mean you can't change the reference's contents. The
reference can't be un-initialized. Hence, in certain cases, a reference can
even extend the lifetime of an object (that doesn't apply here).