STL映射输出迭代器查找值

Question

I am trying to make a function that is generic and takes an output iterator to any container type (that is, a particular kind of map regardless of allocator).

However, I would like to know whether the map referenced by itOut already contains an element, and if so, update it

template<typename OutputIterator>
static void foo(const std::wstring& rstr, OutputIterator itOut)
{
    // Insert two items into the map that itOut references
    itOut++ = TokenPair(t, 1);
    itOut++ = TokenPair(t, 2);

    // This here I don't know how to do
    if(somehow check the map already contains t)
    {
        map[t] = 5;
    }
}

Surely there must be a way for this?

It seems to be the best way because other parts of the program are trying to pass maps that have identical pairs, but different allocators.

Answer 1

I went with the solution that Andy Prowl suggested, where the method is templated to take the appropriate map type. That way the allocator becomes irrelevant.