Chris@16: //  Boost string_algo library collection_traits.hpp header file  -----------------------//
Chris@16: 
Chris@16: //  Copyright Pavol Droba 2002-2003. Use, modification and
Chris@16: //  distribution is subject to the Boost Software License, Version
Chris@16: //  1.0. (See accompanying file LICENSE_1_0.txt or copy at
Chris@16: //  http://www.boost.org/LICENSE_1_0.txt)
Chris@16: 
Chris@16: //  See http://www.boost.org for updates, documentation, and revision history.
Chris@16: 
Chris@16: #ifndef BOOST_RANGE_STRING_DETAIL_COLLECTION_TRAITS_HPP
Chris@16: #define BOOST_RANGE_STRING_DETAIL_COLLECTION_TRAITS_HPP
Chris@16: 
Chris@16: #include <cstddef>
Chris@16: #include <string>
Chris@16: #include <boost/type_traits/is_array.hpp>
Chris@16: #include <boost/type_traits/is_pointer.hpp>
Chris@16: #include <boost/type_traits/is_const.hpp>
Chris@16: #include <boost/type_traits/is_convertible.hpp>
Chris@16: #include <boost/type_traits/remove_pointer.hpp>
Chris@16: #include <boost/type_traits/remove_cv.hpp>
Chris@16: #include <boost/mpl/eval_if.hpp>
Chris@16: #include <boost/mpl/identity.hpp>
Chris@16: #include <boost/mpl/vector.hpp>
Chris@16: #include <boost/mpl/fold.hpp>
Chris@16: #include <boost/detail/iterator.hpp>
Chris@16: 
Chris@16: // Container traits implementation ---------------------------------------------------------
Chris@16: 
Chris@16: namespace boost {
Chris@16:     namespace algorithm {
Chris@16:         namespace detail {
Chris@16: 
Chris@16: // Default collection traits -----------------------------------------------------------------
Chris@16: 
Chris@16:             // Default collection helper 
Chris@16:             /*
Chris@16:                 Wraps std::container compliant containers
Chris@16:             */
Chris@16:             template< typename ContainerT >     
Chris@16:             struct default_container_traits
Chris@16:             {
Chris@101:                 typedef typename ContainerT::value_type value_type;
Chris@101:                 typedef typename ContainerT::iterator iterator;
Chris@101:                 typedef typename ContainerT::const_iterator const_iterator;
Chris@101:                 typedef typename
Chris@16:                     ::boost::mpl::if_< ::boost::is_const<ContainerT>,
Chris@16:                         const_iterator,
Chris@16:                         iterator 
Chris@16:                     >::type result_iterator;
Chris@101:                 typedef typename ContainerT::difference_type difference_type;
Chris@101:                 typedef typename ContainerT::size_type size_type;
Chris@16:                 
Chris@16:                 // static operations
Chris@16:                 template< typename C >
Chris@16:                 static size_type size( const C& c )
Chris@16:                 {
Chris@16:                     return c.size();
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename C >
Chris@16:                 static bool empty( const C& c )
Chris@16:                 {
Chris@16:                     return c.empty();
Chris@16:                 }
Chris@16: 
Chris@16: #ifndef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
Chris@16: 
Chris@16:                 template< typename C >
Chris@16:                 static iterator begin( C& c )
Chris@16:                 {
Chris@16:                     return c.begin();
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename C >
Chris@16:                 static const_iterator begin( const C& c )
Chris@16:                 {
Chris@16:                     return c.begin();
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename C >
Chris@16:                 static iterator end( C& c )
Chris@16:                 {
Chris@16:                     return c.end();
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename C >
Chris@16:                 static const_iterator end( const C& c )
Chris@16:                 {
Chris@16:                     return c.end();
Chris@16:                 }
Chris@16: 
Chris@16: #else // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
Chris@16: 
Chris@16:                 template< typename C >
Chris@16:                 static result_iterator begin( C& c )
Chris@16:                 {
Chris@16:                     return c.begin();
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename C >
Chris@16:                 static result_iterator end( C& c )
Chris@16:                 {
Chris@16:                     return c.end();
Chris@16:                 }
Chris@16: 
Chris@16: #endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING    
Chris@16: 
Chris@16:             }; 
Chris@16: 
Chris@16:             template<typename T>
Chris@16:             struct default_container_traits_selector
Chris@16:             {
Chris@16:                 typedef default_container_traits<T> type;
Chris@16:             };
Chris@16: 
Chris@16: // Pair container traits ---------------------------------------------------------------------
Chris@101: 
Chris@101:             typedef double yes_type;
Chris@101:             typedef char no_type;
Chris@101: 
Chris@16:             // pair selector
Chris@16:             template< typename T, typename U >
Chris@16:             yes_type is_pair_impl( const std::pair<T,U>* );
Chris@16:             no_type is_pair_impl( ... );
Chris@16: 
Chris@16:             template<typename T> struct is_pair
Chris@16:             {
Chris@16:             private:
Chris@16:                 static T* t;
Chris@16:             public:
Chris@16:                 BOOST_STATIC_CONSTANT( bool, value=
Chris@16:                     sizeof(is_pair_impl(t))==sizeof(yes_type) );
Chris@16:             };
Chris@16: 
Chris@16:             // pair helper
Chris@16:             template< typename PairT >
Chris@16:             struct pair_container_traits
Chris@16:             {
Chris@101:                 typedef typename PairT::first_type element_type;
Chris@16: 
Chris@101:                 typedef typename ::boost::detail::
Chris@16:                     iterator_traits<element_type>::value_type value_type;
Chris@16:                 typedef std::size_t size_type;
Chris@101:                 typedef typename ::boost::detail::
Chris@16:                     iterator_traits<element_type>::difference_type difference_type;
Chris@16: 
Chris@16:                 typedef element_type iterator;
Chris@16:                 typedef element_type const_iterator;
Chris@16:                 typedef element_type result_iterator;
Chris@16: 
Chris@16:                 // static operations
Chris@16:                 template< typename P >
Chris@16:                 static size_type size( const P& p )
Chris@16:                 {
Chris@16:                     difference_type diff = std::distance( p.first, p.second );
Chris@16:                     if ( diff < 0 ) 
Chris@16:                         return 0;
Chris@16:                     else
Chris@16:                         return diff;
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename P >
Chris@16:                 static bool empty( const P& p )
Chris@16:                 {
Chris@16:                     return p.first==p.second;
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename P > 
Chris@16:                 static const_iterator begin( const P& p )
Chris@16:                 {
Chris@16:                     return p.first;
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename P >
Chris@16:                 static const_iterator end( const P& p )
Chris@16:                 {
Chris@16:                     return p.second;
Chris@16:                 }
Chris@16:             }; // 'pair_container_helper'
Chris@16: 
Chris@16:             template<typename T>
Chris@16:             struct pair_container_traits_selector
Chris@16:             {
Chris@16:                 typedef pair_container_traits<T> type;
Chris@16:             };
Chris@16: 
Chris@16: // Array container traits ---------------------------------------------------------------
Chris@16: 
Chris@16:             // array traits ( partial specialization )
Chris@16:             template< typename T >
Chris@16:             struct array_traits;
Chris@16: 
Chris@16:             template< typename T, std::size_t sz >
Chris@16:             struct array_traits<T[sz]>
Chris@16:             {
Chris@16:                 // typedef
Chris@16:                 typedef T* iterator;
Chris@16:                 typedef const T* const_iterator;
Chris@16:                 typedef T value_type;
Chris@16:                 typedef std::size_t size_type;
Chris@16:                 typedef std::ptrdiff_t difference_type;
Chris@16: 
Chris@16:                 // size of the array ( static );
Chris@16:                 BOOST_STATIC_CONSTANT( size_type, array_size = sz );
Chris@16:             };
Chris@16: 
Chris@16:             
Chris@16:             // array length resolving
Chris@16:             /*
Chris@16:                 Lenght of string contained in a static array could
Chris@16:                 be different from the size of the array.
Chris@16:                 For string processing we need the length without
Chris@16:                 terminating 0.
Chris@16: 
Chris@16:                 Therefore, the length is calculated for char and wchar_t
Chris@16:                 using char_traits, rather then simply returning
Chris@16:                 the array size.
Chris@16:             */
Chris@16:             template< typename T >
Chris@16:             struct array_length_selector
Chris@16:             {
Chris@16:                 template< typename TraitsT >
Chris@16:                 struct array_length
Chris@16:                 {
Chris@101:                     typedef typename
Chris@16:                         TraitsT::size_type size_type;
Chris@16: 
Chris@16:                     BOOST_STATIC_CONSTANT(
Chris@16:                         size_type,
Chris@16:                         array_size=TraitsT::array_size );
Chris@16: 
Chris@16:                     template< typename A >
Chris@16:                     static size_type length( const A& )
Chris@16:                     {
Chris@16:                         return array_size;
Chris@16:                     }
Chris@16: 
Chris@16:                     template< typename A >
Chris@16:                     static bool empty( const A& )
Chris@16:                     {
Chris@16:                         return array_size==0;
Chris@16:                     }
Chris@16:                 };
Chris@16:             };
Chris@16: 
Chris@16:             // specialization for char
Chris@16:             template<>
Chris@16:             struct array_length_selector<char>
Chris@16:             {
Chris@16:                 template< typename TraitsT >
Chris@16:                 struct array_length
Chris@16:                 {
Chris@101:                     typedef typename
Chris@16:                         TraitsT::size_type size_type;
Chris@16: 
Chris@16:                     template< typename A >
Chris@16:                     static size_type length( const A& a )
Chris@16:                     {
Chris@16:                         if ( a==0 ) 
Chris@16:                             return 0;
Chris@16:                         else
Chris@16:                             return std::char_traits<char>::length(a);
Chris@16:                     }
Chris@16:                     
Chris@16:                     template< typename A >
Chris@16:                     static bool empty( const A& a )
Chris@16:                     {
Chris@16:                         return a==0 || a[0]==0;
Chris@16:                     }
Chris@16:                 };
Chris@16:             };
Chris@16: 
Chris@16:             // specialization for wchar_t
Chris@16:             template<>
Chris@16:             struct array_length_selector<wchar_t>
Chris@16:             {
Chris@16:                 template< typename TraitsT >
Chris@16:                 struct array_length
Chris@16:                 {
Chris@101:                     typedef typename
Chris@16:                         TraitsT::size_type size_type;
Chris@16: 
Chris@16:                     template< typename A >
Chris@16:                     static size_type length( const A& a )
Chris@16:                     {
Chris@16:                         if ( a==0 ) 
Chris@16:                             return 0;
Chris@16:                         else
Chris@16:                             return std::char_traits<wchar_t>::length(a);
Chris@16:                     }
Chris@16: 
Chris@16:                     template< typename A >
Chris@16:                     static bool empty( const A& a )
Chris@16:                     {
Chris@16:                         return a==0 || a[0]==0;
Chris@16:                     }
Chris@16:                 };
Chris@16:             };
Chris@16: 
Chris@16:             template< typename T >
Chris@16:             struct array_container_traits
Chris@16:             {
Chris@16:             private:
Chris@16:                 // resolve array traits
Chris@16:                 typedef array_traits<T> traits_type;
Chris@16: 
Chris@16:             public:
Chris@101:                 typedef typename
Chris@16:                     traits_type::value_type value_type;
Chris@101:                 typedef typename
Chris@16:                     traits_type::iterator iterator;
Chris@101:                 typedef typename
Chris@16:                     traits_type::const_iterator const_iterator;
Chris@101:                 typedef typename
Chris@16:                     traits_type::size_type size_type;
Chris@101:                 typedef typename
Chris@16:                     traits_type::difference_type difference_type;
Chris@16: 
Chris@101:                 typedef typename
Chris@16:                     ::boost::mpl::if_< ::boost::is_const<T>,
Chris@16:                         const_iterator,
Chris@16:                         iterator 
Chris@16:                     >::type result_iterator;
Chris@16:                 
Chris@16:             private:
Chris@16:                 // resolve array size
Chris@101:                 typedef typename
Chris@16:                     ::boost::remove_cv<value_type>::type char_type;
Chris@101:                 typedef typename
Chris@16:                     array_length_selector<char_type>::
Chris@16:                         BOOST_NESTED_TEMPLATE array_length<traits_type> array_length_type;
Chris@16: 
Chris@16:             public:
Chris@16:                 BOOST_STATIC_CONSTANT( size_type, array_size = traits_type::array_size );
Chris@16: 
Chris@16:                 // static operations
Chris@16:                 template< typename A >
Chris@16:                 static size_type size( const A& a )
Chris@16:                 {
Chris@16:                     return array_length_type::length(a);
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename A >
Chris@16:                 static bool empty( const A& a )
Chris@16:                 {
Chris@16:                     return array_length_type::empty(a);
Chris@16:                 }
Chris@16:                 
Chris@16: 
Chris@16: #ifndef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
Chris@16: 
Chris@16:                 template< typename A >
Chris@16:                 static iterator begin( A& a )
Chris@16:                 {
Chris@16:                     return a;
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename A >
Chris@16:                 static const_iterator begin( const A& a )
Chris@16:                 {
Chris@16:                     return a;
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename A >
Chris@16:                 static iterator end( A& a )
Chris@16:                 {
Chris@16:                     return a+array_length_type::length(a);
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename A >
Chris@16:                 static const_iterator end( const A& a )
Chris@16:                 {
Chris@16:                     return a+array_length_type::length(a);
Chris@16:                 }
Chris@16: 
Chris@16: #else // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
Chris@16: 
Chris@16:                 template< typename A >
Chris@16:                 static result_iterator begin( A& a )
Chris@16:                 {
Chris@16:                     return a;
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename A >
Chris@16:                 static result_iterator end( A& a )
Chris@16:                 {
Chris@16:                     return a+array_length_type::length(a);
Chris@16:                 }
Chris@16: 
Chris@16: #endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING    
Chris@16: 
Chris@16:             }; 
Chris@16: 
Chris@16:             template<typename T>
Chris@16:             struct array_container_traits_selector
Chris@16:             {
Chris@16:                 typedef array_container_traits<T> type;
Chris@16:             };
Chris@16: 
Chris@16: // Pointer container traits ---------------------------------------------------------------
Chris@16: 
Chris@16:             template<typename T>
Chris@16:             struct pointer_container_traits
Chris@16:             {
Chris@101:                 typedef typename
Chris@16:                     ::boost::remove_pointer<T>::type value_type;
Chris@16: 
Chris@101:                 typedef typename
Chris@16:                     ::boost::remove_cv<value_type>::type char_type;
Chris@16:                 typedef ::std::char_traits<char_type> char_traits;
Chris@16: 
Chris@16:                 typedef value_type* iterator;
Chris@16:                 typedef const value_type* const_iterator;
Chris@16:                 typedef std::ptrdiff_t difference_type;
Chris@16:                 typedef std::size_t size_type;
Chris@16: 
Chris@101:                 typedef typename
Chris@16:                     ::boost::mpl::if_< ::boost::is_const<T>,
Chris@16:                         const_iterator,
Chris@16:                         iterator 
Chris@16:                     >::type result_iterator;
Chris@16: 
Chris@16:                 // static operations
Chris@16:                 template< typename P >
Chris@16:                 static size_type size( const P& p )
Chris@16:                 {
Chris@16:                     if ( p==0 ) 
Chris@16:                         return 0;
Chris@16:                     else
Chris@16:                         return char_traits::length(p);
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename P >
Chris@16:                 static bool empty( const P& p )
Chris@16:                 {
Chris@16:                     return p==0 || p[0]==0;
Chris@16:                 }
Chris@16: 
Chris@16: #ifndef BOOST_NO_FUNCTION_TEMPLATE_ORDERING
Chris@16: 
Chris@16:                 template< typename P >
Chris@16:                 static iterator begin( P& p )
Chris@16:                 {
Chris@16:                     return p;
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename P >
Chris@16:                 static const_iterator begin( const P& p )
Chris@16:                 {
Chris@16:                     return p;
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename P >
Chris@16:                 static iterator end( P& p )
Chris@16:                 {
Chris@16:                     if ( p==0 )
Chris@16:                         return p;
Chris@16:                     else
Chris@16:                         return p+char_traits::length(p);
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename P >
Chris@16:                 static const_iterator end( const P& p )
Chris@16:                 {
Chris@16:                     if ( p==0 )
Chris@16:                         return p;
Chris@16:                     else
Chris@16:                         return p+char_traits::length(p);
Chris@16:                 }
Chris@16: 
Chris@16: #else // BOOST_NO_FUNCTION_TEMPLATE_ORDERING
Chris@16: 
Chris@16:                 template< typename P >
Chris@16:                 static result_iterator begin( P& p )
Chris@16:                 {
Chris@16:                     return p;
Chris@16:                 }
Chris@16: 
Chris@16:                 template< typename P >
Chris@16:                 static result_iterator end( P& p )
Chris@16:                 {
Chris@16:                     if ( p==0 )
Chris@16:                         return p;
Chris@16:                     else
Chris@16:                         return p+char_traits::length(p);
Chris@16:                 }
Chris@16: 
Chris@16: #endif // BOOST_NO_FUNCTION_TEMPLATE_ORDERING    
Chris@16:             }; 
Chris@16: 
Chris@16:             template<typename T>
Chris@16:             struct pointer_container_traits_selector
Chris@16:             {
Chris@16:                 typedef pointer_container_traits<T> type;
Chris@16:             };
Chris@16: 
Chris@16:         } // namespace detail
Chris@16:     } // namespace algorithm
Chris@16: } // namespace boost
Chris@16: 
Chris@16: 
Chris@16: #endif  // BOOST_STRING_DETAIL_COLLECTION_HPP