Hi,
Can someone please explain what a copy constructor does and how it's
useful? Thanks,
Terry
4  3204 
"Terry" <te***@nospam.c om> wrote in message
news:3f******** @clarion.carno. net.au... Hi,
Can someone please explain what a copy constructor does and how it's
useful? Thanks,
It constructs an object (like the regular c'tor) from an already
existing object. This way you avoid first constructing and then assigning
(ie. two steps, instead of one).
hth
--
jb
(replace y with x if you want to reply by e-mail) Hi,
Can someone please explain what a copy constructor does and how it's
useful? Thanks,
It constructs an object (like the regular c'tor) from an already
existing object. This way you avoid first constructing and then assigning
(ie. two steps, instead of one).
can't you use use the assignment operator to copy? that should be one step
as well.
asasas
"A" <A@iprimus.com. au> wrote...
Hi,
Can someone please explain what a copy constructor does and how it's
useful? Thanks,
It constructs an object (like the regular c'tor) from an already
existing object. This way you avoid first constructing and then
assigning (ie. two steps, instead of one).
can't you use use the assignment operator to copy? that should be one step
as well.
No. Assignment operator is useless when passing parameters by
value or returning by value is concerned. Those are the main
uses of the copy constructor.
Victor
"A" <A@iprimus.com. au> wrote in message
news:3f******** @news.iprimus.c om.au...
Hi,
Can someone please explain what a copy constructor does and how it's
useful? Thanks,
It constructs an object (like the regular c'tor) from an already
existing object. This way you avoid first constructing and then
assigning (ie. two steps, instead of one).
can't you use use the assignment operator to copy? that should be one step
as well.
asasas
A a;
A b(a); // copy construct, one step
A c; // default construct, step 1
c = a; // assign, step 2
Creating a copy of an object using assignment uses two steps, first the
object is constructed, then it is assigned.
john This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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A default copy constructor is created for you when you don't specify one
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