Question

I am currently working on implementing the constructor function for the vector class(my professor said that we can leave out anything that uses an allocator). I used the reference website that my professor gave us to determine the format of the function: http://www.cplusplus.com/reference/stl/vector/vector/

I am getting some errors in my function. Two of the errors are:

syntax error: identifier ‘size_type’

‘value’ : undeclared identifier

Any idea why I would be getting these errors? Here is my code:

explicit vector (size_type n, const T& value= T())
{
    my_vect=new int x[2*n];
    for(int i=0; i<n; i++)
    {
        vect[i]=value;
        length++;
    }
}

Answer 1

If you define your class in an .h file, then the = T() is the default value. When you implement the method in the .cpp or .cc file, you leave out the default value.

size_type is not in global scope it seems, so you need to use the resolution operator to give it correct scope. It appears to be std::string::size_type. This is probably just a typedef for size_t. I see size_type in the STL containers, but I’ve never used it when creating my own classes.

Also, as Dietmar Kühl mentioned, when using C++ templates, you need to decorate everything with template <typename T>