Template class with variable parameters.

This is a discussion on Template class with variable parameters. within the C++ Programming forums, part of the General Programming Boards category; Suppose I have a template class: Code: template<class A, int B> class foo { ..... } is it possible to ...

  1. #1
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    Template class with variable parameters.

    Suppose I have a template class:
    Code:
    template<class A, int B>
    class foo
    {
    .....
    }
    is it possible to instantiate the template class with a variable in the second paramter?
    int variable=99;
    foo<apples, variable> foo1=new foo();
    , where apples is a class.

    My compiler doesn't let me do it as above; it requires the second parameter to be a constant.

    Thanks.
    Last edited by cybernike; 06-29-2007 at 10:41 PM.

  2. #2
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    It must be a compile-time constant. Templates are resolved at compile time. A different class foo is created for each different set of parameters you give it, so the compiler must know the parameter values when it is compiling.

  3. #3
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    I do not think so, since the template must be instantiated at compile type, and a variable's value may be determined at runtime.
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