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#### equal_to

##### Description

Returns a true-valued MPL Integral Constant if `I` and `J` are equal.

##### Synopsis

    template<
        typename I,
        typename J
        >
    struct equal_to
    {
        typedef unspecified type;
    };

Table 1.15. Parameters

Parameter | Requirement | Description
--- | --- | ---
`I`, `J` | Any fusion iterators | Operation's arguments

##### Expression Semantics

    result_of::equal_to<I, J>::type

Return type: A model of MPL Integral Constant.

Semantics: Returns `boost::mpl::true_` if `I` and `J` are iterators to the same position. Returns `boost::mpl::false_` otherwise.

##### Header

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

##### Example

    typedef vector<int,double> vec;
    typedef result_of::begin<vec>::type first;
    typedef result_of::end<vec>::type last;
    BOOST_MPL_ASSERT((result_of::equal_to<first, first>));
    BOOST_MPL_ASSERT_NOT((result_of::equal_to<first,last>));