Standard C++ Library Class Reference

used to instantiate the iterator. The fifth version takes and returns a T* in order to handle the case

when an iterator is a simple pointer.

This family of function templates can be used to extract a value type from an iterator and

subsequently use that type to create a local variable. Typically the value_type functions are used

like this:

template <class Iterator>

void foo(Iterator first, Iterator last)

{

__foo(begin,end,value_type(first));

}

template <class Iterator, class T>

void __foo(Iterator first, Iterator last, T*>

{

T temp = *first;

}

The auxiliary function __foo extracts a usable value type from the iterator and then puts the type

to work.