CppCoreGuidelines T.60 减少模板上下文依赖关系

template<typename C>
void sort(C& c)
{
    std::sort(begin(c), end(c)); // necessary and useful dependency
}

template<typename Iter>
Iter algo(Iter first, Iter last)
{
    for (; first != last; ++first) {
        auto x = sqrt(*first); // potentially surprising dependency: which sqrt()?
        helper(first, x);      // potentially surprising dependency:
                               // helper is chosen based on first and x
        TT var = 7;            // potentially surprising dependency: which TT?
    }
}