C++ template using pointer and non pointer arguments in a QVector

Question

I'm trying to avoid having to use "nearly" the same code twice. I have the following template function, which searches for the provided value in a QVector and returns the index to the element.

template<class tVec,class tVal>
int upperBoundIndex(const QVector<tVec> &vec,int first,int last,tVal value)
{
//code here
}

Searching for example a vector of the following type works fine: QVector<int>, however I'd like to also be able to search a vector of the type QVector<int*>, so I wrote another template function.

template<class tVec,class tVal>
int upperBoundIndex(const QVector<tVec*> &vec,int first,int last,tVal value)
{
//similar code here, but the dereferencing
}

This also works fine, but I've been wondering, is there a way I can use the same code for both functions? Because I nearly copy and pasted the code from one function to the other, and so far whenever I changed something in one function I, jumped right to the other and applied the same changes, is there a more optimal solution?

p.s. I'm not looking for alternative search functions, I know there are search functions for example in the std namespace. I'd like to know if there's a way to optimize my approach.

Answer 1

You could template your container Qvector and make it more generic with something like :

template<class Container>
int upperBoundIndex(const Container &vec,int first,int last,typename Container::value_type value)
{
 // your code
}

But I think you should use std::upper_bound where you even have an example to get the index.

So I would use this kind of reusable function instead :

template<class ForwardIt, class T>
T upperBoundIndex(ForwardIt first, ForwardIt last, const T& value)
{
    return (std::upper_bound (first, last, value) - first);
}

Live example