deref

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#### deref

###### Description

Returns the type that will be returned by dereferencing an iterator.

###### Synposis

    template<
        typename I
        >
    struct deref
    {
        typedef unspecified type;
    };

Table 1.12. Parameters

Parameter | Requirement | Description
--- | --- | ---
`I` | Model of Forward Iterator | Operation's argument

###### Expression Semantics

    result_of::deref<I>::type

Return type: Any type

Semantics: Returns the result of dereferencing an iterator of type `I`.

###### Header

    #include <boost/fusion/iterator/deref.hpp>
    #include <boost/fusion/include/deref.hpp>

###### Example

    typedef vector<int,int&> vec;
    typedef const vec const_vec;
    typedef result_of::begin<vec>::type first;
    typedef result_of::next<first>::type second;

    typedef result_of::begin<const_vec>::type const_first;
    typedef result_of::next<const_first>::type const_second;

    BOOST_MPL_ASSERT((boost::is_same<result_of::deref<first>::type, int&>));
    BOOST_MPL_ASSERT((boost::is_same<result_of::deref<second>::type, int&>));