sequence.qbk

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[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
]

[heading Expression Semantics]
    result_of::end<Seq>::type

[*Return type]: A model of the same traversal concept as `Seq`.

[*Semantics]: Returns the type of an iterator one past the end of `Seq`.

/sequence/intrinsic/end.hpp>

[heading Example]
    typedef __vector__<int> vec;
    typedef __result_of_prior__<__result_of_end__<vec>::type>::type first;
    BOOST_MPL_ASSERT((__result_of_equal_to__<first, __result_of_begin__<vec>::type>))

[endsect]

[section empty]

[heading Description]
Returns the result type of __empty__.

[heading Synopsis]
    template<typename Seq>
    struct empty
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
]

[heading Expression Semantics]
    result_of::empty<Seq>::type

[*Return type]: An __mpl_integral_constant__

[*Semantics]: Returns `mpl::true_` if `Seq` has zero elements, `mpl::false_` otherwise.

/sequence/intrinsic/empty.hpp>

[heading Example]
    typedef __vector__<> empty_vec;
    typedef __vector__<int,float,char> vec;

    BOOST_MPL_ASSERT((__result_of_empty__<empty_vec>));
    BOOST_MPL_ASSERT_NOT((__result_of_empty__<vec>));

[endsect]

[section front]

[heading Description]
Returns the result type of __front__.

[heading Synopsis]
    template<typename Seq>
    struct front
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
]

[heading Expression Semantics]
    result_of::front<Seq>::type

[*Return type]: Any type

[*Semantics]: The type returned by dereferencing an iterator to the first element in `Seq`. Equivalent to `__result_of_deref__<__result_of_begin__<Seq>::type>::type`.

/sequence/intrinsic/front.hpp>

[heading Example]
    typedef __vector__<int,char> vec;
    BOOST_MPL_ASSERT((boost::is_same<__result_of_front__<vec>::type, int&>));

[endsect]

[section back]

[heading Description]
Returns the result type of __back__.

[heading Synopsis]
    template<typename Seq>
    struct back
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
]

[heading Expression Semantics]
    result_of::back<Seq>::type

[*Return type]:  Any type

[*Semantics]: The type returned by dereferencing an iterator to the last element in the sequence. Equivalent to `__result_of_deref__<__result_of_prior__<__result_of_end__<Seq>::type>::type>::type`.

/sequence/intrinsic/back.hpp>

[heading Example]
    typedef __vector__<int,char> vec;
    BOOST_MPL_ASSERT((boost::is_same<__result_of_back__<vec>::type, char&>));

[endsect]

[section size]

[heading Description]
Returns the result type of __size__.

[heading Synopsis]
    template<typename Seq>
    struct size
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
]

[heading Expression Semantics]
    result_of::size<Seq>::type

[*Return type]: An __mpl_integral_constant__.

[*Semantics]: Returns the number of elements in `Seq`.

/sequence/intrinsic/size.hpp>

[heading Example]
    typedef __vector__<int,float,char> vec;
    typedef __result_of_size__<vec>::type size_mpl_integral_constant;
    BOOST_MPL_ASSERT_RELATION(size_mpl_integral_constant::value, ==, 3);

[endsect]

[section at]

[heading Description]

Returns the result type of __at__[footnote __result_of_at__ reflects the
actual return type of the function __at__. __sequence__(s) typically return
references to its elements via the __at__ function. If you want to get
the actual element type, use __result_of_value_at__].

[heading Synopsis]
    template<
        typename Seq,
        typename N>
    struct at
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
    [[`N`][An __mpl_integral_constant__][Index of element]]
]

[heading Expression Semantics]
    result_of::at<Seq, N>::type

[*Return type]: Any type.

[*Semantics]: Returns the result type of using __at__ to access the `N`th element of `Seq`.

/sequence/intrinsic/at.hpp>

[heading Example]
    typedef __vector__<int,float,char> vec;
    BOOST_MPL_ASSERT((boost::is_same<__result_of_at__<vec, boost::mpl::int_<1> >::type, float&>));

[endsect]

[section at_c]

[heading Description]

Returns the result type of __at_c__[footnote __result_of_at_c__ reflects
the actual return type of the function __at_c__. __sequence__(s) typically
return references to its elements via the __at_c__ function. If you want to
get the actual element type, use __result_of_value_at_c__].

[heading Synopsis]
    template<
        typename Seq,
        int M>
    struct at_c
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
    [[`M`][Positive integer index][Index of element]]
]

[heading Expression Semantics]
    result_of::at_c<Seq, M>::type

[*Return type]: Any type

[*Semantics]: Returns the result type of using __at_c__ to access the `M`th element of `Seq`.

/sequence/intrinsic/at.hpp>

[heading Example]
    typedef __vector__<int,float,char> vec;
    BOOST_MPL_ASSERT((boost::is_same<__result_of_at_c__<vec, 1>::type, float&>));

[endsect]

[section value_at]

[heading Description]

Returns the actual type at a given index from the __sequence__.

[heading Synopsis]
    template<
        typename Seq,
        typename N>
    struct value_at
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
    [[`N`][An __mpl_integral_constant__][Index of element]]
]

[heading Expression Semantics]
    result_of::value_at<Seq, N>::type

[*Return type]: Any type.

[*Semantics]: Returns the actual type at the `N`th element of `Seq`.

/sequence/intrinsic/value_at.hpp>

[heading Example]
    typedef __vector__<int,float,char> vec;
    BOOST_MPL_ASSERT((boost::is_same<__result_of_value_at__<vec, boost::mpl::int_<1> >::type, float>));

[endsect]

[section value_at_c]

[heading Description]

Returns the actual type at a given index from the __sequence__.

[heading Synopsis]
    template<
        typename Seq,
        int M>
    struct value_at_c
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
    [[`M`][Positive integer index][Index of element]]
]

[heading Expression Semantics]
    result_of::value_at_c<Seq, M>::type

[*Return type]: Any type

[*Semantics]: Returns the actual type at the `M`th element of `Seq`.

/sequence/intrinsic/value_at.hpp>

[heading Example]
    typedef __vector__<int,float,char> vec;
    BOOST_MPL_ASSERT((boost::is_same<__result_of_value_at_c__<vec, 1>::type, float>));

[endsect]

[section has_key]

[heading Description]
Returns the result type of __has_key__.

[heading Synopsis]
    template<
        typename Seq,
        typename Key>
    struct has_key
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
    [[`Key`][Any type][Key type]]
]

[heading Expression Semantics]
    result_of::has_key<Seq, Key>::type

[*Return type]: An __mpl_integral_constant__.

[*Semantics]: Returns `mpl::true_` if `Seq` contains an element with key type `Key`, returns `mpl::false_` otherwise.

/sequence/intrinsic/has_key.hpp>

[heading Example]
    typedef __map__<__pair__<int, char>, __pair__<char, char>, __pair__<double, char> > mymap;
    BOOST_MPL_ASSERT((__result_of_has_key__<mymap, int>));
    BOOST_MPL_ASSERT_NOT((__result_of_has_key__<mymap, void*>));

[endsect]

[section at_key]

[heading Description]

Returns the result type of __at_key__[footnote __result_of_at_key__
reflects the actual return type of the function __at_key__. __sequence__s
typically return references to its elements via the __at_key__ function. If
you want to get the actual element type, use __result_of_value_at_key__].

[heading Synopsis]
    template<
        typename Seq,
        typename Key>
    struct at_key
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
    [[`Key`][Any type][Key type]]
]

[heading Expression Semantics]
    result_of::at_key<Seq, Key>::type

[*Return type]: Any type.

[*Semantics]: Returns the result of using __at_key__ to access the element with key type `Key` in `Seq`.

/sequence/intrinsic/at_key.hpp>

[heading Example]
    typedef __map__<__pair__<int, char>, __pair__<char, char>, __pair__<double, char> > mymap;
    BOOST_MPL_ASSERT((boost::is_same<__result_of_at_key__<mymap, int>::type, char&>));

[endsect]

[section value_at_key]

[heading Description]
Returns the actual element type associated with a Key from the __sequence__.

[heading Synopsis]
    template<
        typename Seq,
        typename Key>
    struct value_at_key
    {
        typedef __unspecified__ type;
    };

[table Parameters
    [[Parameter]    [Requirement]   [Description]]
    [[`Seq`][A model of __forward_sequence__][Argument sequence]]
    [[`Key`][Any type][Key type]]
]

[heading Expression Semantics]
    result_of::value_at_key<Seq, Key>::type

[*Return type]: Any type.

[*Semantics]: Returns the actual element type associated with key type
`Key` in `Seq`.

/sequence/intrinsic/value_at_key.hpp>

[heading Example]
    typedef __map__<__pair__<int, char>, __pair__<char, char>, __pair__<double, char> > mymap;
    BOOST_MPL_ASSERT((boost::is_same<__result_of_at_key__<mymap, int>::type, char>));

[endsect]

[section swap]

[heading Description]
Returns the return type of swap.

[heading Synopsis]
    template<typename Seq1, typename Seq2>
    struct swap
    {
        typedef void type;
    };

[table Parameters
    [[Parameters]    [Requirement]   [Description]]
    [[`Seq1`, `Seq2`][Models of __forward_sequence__][The sequences being swapped]]
]

[heading Expression Semantics]
    result_of::swap<Seq1, Seq2>::type

[*Return type]: `void`.

[*Semantics]: Always returns `void`.

/sequence/intrinsic/swap.hpp>

[endsect]

[endsect]

[endsect]

[section Operator]

These operators, like the __algorithms__, work generically on all Fusion
sequences. All conforming Fusion sequences automatically get these
operators for free.

[section I/O]

The I/O operators: `<<` and `>>` work generically on all Fusion sequences.
The global `operator<<` has been overloaded for generic output streams such