Help me understand copying better

This is a discussion on Help me understand copying better within the C++ Programming forums, part of the General Programming Boards category; It doesn't. It uses a built-in assignment operator instead. No, it uses the compiler provided copy constructor. In that case ...

  1. #16
    C++ Witch laserlight's Avatar
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    It doesn't. It uses a built-in assignment operator instead.
    No, it uses the compiler provided copy constructor.

    In that case the compiler is allowed to also use the copy-constructor, instead of a call to the default constructor followed by a call to the assignment operator. So you can't actually say that it will call the assignment operator. It's compiler dependent.
    I do not have a copy of the C++ Standard with me at the moment, but I believe that it is not compiler dependent: this syntax means an implicit invocation of the copy constructor. If you declare the copy constructor explicit, then one must use:
    Code:
    SomeObject object2(object1);
    instead of:
    Code:
    SomeObject object2 = object1;
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  2. #17
    C++まいる!Cをこわせ!
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    Quote Originally Posted by laserlight View Post
    No, it uses the compiler provided copy constructor.
    Gah, yes, I wrote the wrong thing >_<
    Stupid mistakes >_<

  3. #18
    Algorithm Dissector iMalc's Avatar
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    Quote Originally Posted by laserlight View Post
    I do not have a copy of the C++ Standard with me at the moment, but I believe that it is not compiler dependent: this syntax means an implicit invocation of the copy constructor.
    You could be right. I can't confirm it either.
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  4. #19
    Officially An Architect brewbuck's Avatar
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    Quote Originally Posted by force of will View Post
    In VS 8 it prints "assign!", in gcc it prints nothing, so maybe compiler depend or non standard feature, although im more inclined to the second one
    Wow. I guess I'll never be using that compiler then, as that is absolutely, critically broken.

  5. #20
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    Quote Originally Posted by brewbuck View Post
    Wow. I guess I'll never be using that compiler then, as that is absolutely, critically broken.
    My bad i just deleted that post, im guessing im seeing things lol :P

  6. #21
    C++まいる!Cをこわせ!
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    I can't find that VC++ calls the assignment operator instead of the copy constructor. The "print" test prints nothing, so there shouldn't be anything wrong with the compiler.

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