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assigning an array

Posted on 1998-07-13
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Last Modified: 2010-04-01
i have an array class and i want to be able to initialize the array with a string of values or variable names, much like:

array<int> AnArray(6) = {1, 2, 3, 4, 5, 6};

or

array<int> AnArray(6);
AnArray.AssignArray(1, 2, 3, 4, 5, 6);

i have tried to do this but have the following problem.  if i made an AssignArray function it would have to take a variable number of parameters because different arrays have different number of elements.  i know overloading would take care of this but it would get tedious to make the same function over and over changing only the number of arguments, especially with arrays of hundreds of elements.  
do any of you know a better way to do this?
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Question by:Booth882
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alexo earned 80 total points
ID: 1167620
There are several issues at work here.

First, a class can be initialized by an initialization list *only if* it does not have constructors, private or protected members, base classes, or virtual functions.

Second, a constructor (like any other function) can take a variable number of arguments.

For example:


    #include <stdarg.h>

    const int ArraySize = 5;

    class Array
    {
    public:
        Array(int, ...);

    private:
        int a[ArraySize];
    };


    Array::Array(int num, ...)
    {
        va_list args;
        va_start(args, num);
        for (int i = 0; i < num; ++i)
            a[i] = va_arg(args, int);
        va_end(args);
    }

    int main()
    {
        Array a(ArraySize, 1, 2, 3, 4, 5);

        return 0;
    }

Note however that no compile-time checking will be done on the arguments represented by the "..."
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by:Booth882
ID: 1167621
thank you much!
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