constructors in arrays

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  1. #1
    l'Anziano DavidP's Avatar
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    Question constructors in arrays

    When you declare an instance of a class, why are you only allowed to use the default constructor of that class? For example:

    class A{
    public:
    A ( ); //default
    A ( int j );
    int myInt;
    }

    legal:

    A myArray[5];

    illegal:

    A myArray[5](10);
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  2. #2
    _B-L-U-E_ Betazep's Avatar
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    you don't have to use the default constructor. You can make an assortment of constructors to do whatever you want depending on what is passed.

    ...
    A(int this)
    {
    my_private_member_data = this;
    }
    ....


    then

    A instantiation[5](2);

    is valid.
    Last edited by Betazep; 12-06-2001 at 10:37 PM.
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  3. #3
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    A instantiation[5](2);

    is valid.
    no, it's not valid...

  4. #4
    It's full of stars adrianxw's Avatar
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    The problem with...

    >>> A instantiation[5](2);

    ... is ambiguity, which member of the array will have the value 2? The correct way to do this is...

    A instatiation[5] = {2,2,2,2,2};

    ... one value for each constructor, no ambiguity.
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