boost/iostreams/input_sequence.hpp

   1 // (C) Copyright 2008 CodeRage, LLC (turkanis at coderage dot com)
   2 // (C) Copyright 2003-2007 Jonathan Turkanis
   3 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   4 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt.)
   5
   6 // See http://www.boost.org/libs/iostreams for documentation.
   7
   8 #ifndef BOOST_IOSTREAMS_INPUT_SEQUENCE_HPP_INCLUDED
   9 #define BOOST_IOSTREAMS_INPUT_SEQUENCE_HPP_INCLUDED
  10
  11 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
  12 # pragma once
  13 #endif
  14
  15 #include <utility>           // pair.
  16 #include <boost/config.hpp>  // DEDUCED_TYPENAME, MSVC.
  17 #include <boost/detail/workaround.hpp>
  18 #include <boost/iostreams/detail/wrap_unwrap.hpp>
  19 #include <boost/iostreams/operations_fwd.hpp>  // is_custom
  20 #include <boost/iostreams/traits.hpp>
  21 #include <boost/mpl/if.hpp>
  22
  23 // Must come last.
  24 #include <boost/iostreams/detail/config/disable_warnings.hpp>
  25
  26 namespace boost { namespace iostreams {
  27
  28 namespace detail {
  29
  30 template<typename T>
  31 struct input_sequence_impl;
  32
  33 } // End namespace detail.
  34
  35 template<typename T>
  36 inline std::pair<
  37     BOOST_DEDUCED_TYPENAME char_type_of<T>::type*,
  38     BOOST_DEDUCED_TYPENAME char_type_of<T>::type*
  39 >
  40 input_sequence(T& t)
  41 { return detail::input_sequence_impl<T>::input_sequence(t); }
  42
  43 namespace detail {
  44
  45 //------------------Definition of direct_impl-------------------------------//
  46
  47 template<typename T>
  48 struct input_sequence_impl
  49     : mpl::if_<
  50           detail::is_custom<T>,
  51           operations<T>,
  52           input_sequence_impl<direct_tag>
  53       >::type
  54     { };
  55
  56 template<>
  57 struct input_sequence_impl<direct_tag> {
  58     template<typename U>
  59     static std::pair<
  60         BOOST_DEDUCED_TYPENAME char_type_of<U>::type*,
  61         BOOST_DEDUCED_TYPENAME char_type_of<U>::type*
  62     >
  63     input_sequence(U& u) { return u.input_sequence(); }
  64 };
  65
  66 } // End namespace detail.
  67
  68 } } // End namespaces iostreams, boost.
  69
  70 #include <boost/iostreams/detail/config/enable_warnings.hpp>
  71
  72 #endif // #ifndef BOOST_IOSTREAMS_INPUT_SEQUENCE_HPP_INCLUDED