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From: worlman385 on 17 Apr 2008 19:44
==== [Non-pointer version] ====
as a rule, for non pointer, as long as I have an object that dont'
need to pass to another function / call another function. I can do the
following (non-pointer) -

Database db;
db.open("user", "pass");


==== [Pointer version] ====
If I need to pass the object to another function then I should use
(pointer) -
Database* db = new Database();
bool flag = openConnection ( db, "user", "pass" );


==== [pointer version (reference)] ====
If I need to pass the object to another function then I can also use
(reference) -
Database db;
bool flag = openConnection ( db, "user", "pass" );

by doing method #1 and #3, i can avoid pointer most of the time?

then I will not need to worry about delete / free pointer after using
it.


From: Igor Tandetnik on 17 Apr 2008 19:59
worlman385(a)yahoo.com wrote:
> ==== [Non-pointer version] ====
> as a rule, for non pointer, as long as I have an object that dont'
> need to pass to another function / call another function. I can do the
> following (non-pointer) -
>
> Database db;
> db.open("user", "pass");
>
>
> ==== [Pointer version] ====
> If I need to pass the object to another function then I should use
> (pointer) -
> Database* db = new Database();
> bool flag = openConnection ( db, "user", "pass" );

Not necessarily. You can do

Database db;
bool flag = openConnection (&db, "user", "pass" );

Whether or not to allocate on the heap depends on whether you want the
object to outlive the current scope, not whether you need a pointer to
it.

> ==== [pointer version (reference)] ====
> If I need to pass the object to another function then I can also use
> (reference) -
> Database db;
> bool flag = openConnection ( db, "user", "pass" );

And also

Database* db = new Database();
bool flag = openConnection (*db, "user", "pass" );

Just to demonstrate again that the choice of allocating on the stack or
on the heap has nothing to do with whether some function wants a pointer
or a reference.
--
With best wishes,
Igor Tandetnik

With sufficient thrust, pigs fly just fine. However, this is not
necessarily a good idea. It is hard to be sure where they are going to
land, and it could be dangerous sitting under them as they fly
overhead. -- RFC 1925


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