Method IteratorGenerator

CvPlot/ext/catch2/inc/catch.hpp:4662–4666

public:
    template <typename InputIterator, typename InputSentinel>
    IteratorGenerator(InputIterator first, InputSentinel last):m_elems(first, last) {
        if (m_elems.empty()) {
            Catch::throw_exception(GeneratorException("IteratorGenerator received no valid values"));
        }
    }

    T const& get() const override {
        return m_elems[m_current];