Chris@16: /*=============================================================================
Chris@16:     Copyright (c) 2001-2011 Joel de Guzman
Chris@16:     Copyright (c) 2001-2011 Hartmut Kaiser
Chris@16:     Copyright (c)      2010 Bryce Lelbach
Chris@16: 
Chris@16:     Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16:     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: ================================================_==============================*/
Chris@16: #if !defined(BOOST_SPIRIT_STRING_TRAITS_OCTOBER_2008_1252PM)
Chris@16: #define BOOST_SPIRIT_STRING_TRAITS_OCTOBER_2008_1252PM
Chris@16: 
Chris@16: #if defined(_MSC_VER)
Chris@16: #pragma once
Chris@16: #endif
Chris@16: 
Chris@16: #include <boost/spirit/home/support/container.hpp>
Chris@16: #include <string>
Chris@16: #include <boost/mpl/bool.hpp>
Chris@16: #include <boost/mpl/identity.hpp>
Chris@16: #include <boost/mpl/if.hpp>
Chris@16: #include <boost/proto/proto_fwd.hpp>
Chris@16: #include <boost/type_traits/is_const.hpp>
Chris@16: #if defined(__GNUC__) && (__GNUC__ < 4)
Chris@16: #include <boost/type_traits/add_const.hpp>
Chris@16: #endif
Chris@16: 
Chris@16: namespace boost { namespace spirit { namespace traits
Chris@16: {
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // Determine if T is a character type
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename T>
Chris@16:     struct is_char : mpl::false_ {};
Chris@16: 
Chris@16:     template <typename T>
Chris@16:     struct is_char<T const> : is_char<T> {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct is_char<char> : mpl::true_ {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct is_char<wchar_t> : mpl::true_ {};
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // Determine if T is a string
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename T>
Chris@16:     struct is_string : mpl::false_ {};
Chris@16: 
Chris@16:     template <typename T>
Chris@16:     struct is_string<T const> : is_string<T> {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct is_string<char const*> : mpl::true_ {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct is_string<wchar_t const*> : mpl::true_ {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct is_string<char*> : mpl::true_ {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct is_string<wchar_t*> : mpl::true_ {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct is_string<char[N]> : mpl::true_ {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct is_string<wchar_t[N]> : mpl::true_ {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct is_string<char const[N]> : mpl::true_ {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct is_string<wchar_t const[N]> : mpl::true_ {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct is_string<char(&)[N]> : mpl::true_ {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct is_string<wchar_t(&)[N]> : mpl::true_ {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct is_string<char const(&)[N]> : mpl::true_ {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct is_string<wchar_t const(&)[N]> : mpl::true_ {};
Chris@16: 
Chris@16:     template <typename T, typename Traits, typename Allocator>
Chris@16:     struct is_string<std::basic_string<T, Traits, Allocator> > : mpl::true_ {};
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // Get the underlying char type of a string
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename T>
Chris@16:     struct char_type_of;
Chris@16: 
Chris@16:     template <typename T>
Chris@16:     struct char_type_of<T const> : char_type_of<T> {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct char_type_of<char> : mpl::identity<char> {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct char_type_of<wchar_t> : mpl::identity<wchar_t> {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct char_type_of<char const*> : mpl::identity<char const> {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct char_type_of<wchar_t const*> : mpl::identity<wchar_t const> {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct char_type_of<char*> : mpl::identity<char> {};
Chris@16: 
Chris@16:     template <>
Chris@16:     struct char_type_of<wchar_t*> : mpl::identity<wchar_t> {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct char_type_of<char[N]> : mpl::identity<char> {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct char_type_of<wchar_t[N]> : mpl::identity<wchar_t> {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct char_type_of<char const[N]> : mpl::identity<char const> {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct char_type_of<wchar_t const[N]> : mpl::identity<wchar_t const> {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct char_type_of<char(&)[N]> : mpl::identity<char> {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct char_type_of<wchar_t(&)[N]> : mpl::identity<wchar_t> {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct char_type_of<char const(&)[N]> : mpl::identity<char const> {};
Chris@16: 
Chris@16:     template <std::size_t N>
Chris@16:     struct char_type_of<wchar_t const(&)[N]> : mpl::identity<wchar_t const> {};
Chris@16: 
Chris@16:     template <typename T, typename Traits, typename Allocator>
Chris@16:     struct char_type_of<std::basic_string<T, Traits, Allocator> >
Chris@16:       : mpl::identity<T> {};
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // Get the C string from a string
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     template <typename String>
Chris@16:     struct extract_c_string;
Chris@16: 
Chris@16:     template <typename String>
Chris@16:     struct extract_c_string
Chris@16:     {
Chris@16:         typedef typename char_type_of<String>::type char_type;
Chris@16: 
Chris@16:         template <typename T>
Chris@16:         static T const* call (T* str)
Chris@16:         {
Chris@16:             return (T const*)str; 
Chris@16:         }
Chris@16: 
Chris@16:         template <typename T>
Chris@16:         static T const* call (T const* str)
Chris@16:         {
Chris@16:             return str; 
Chris@16:         }
Chris@16:     }; 
Chris@16:     
Chris@16:     // Forwarder that strips const
Chris@16:     template <typename T>
Chris@16:     struct extract_c_string<T const>
Chris@16:     {
Chris@16:         typedef typename extract_c_string<T>::char_type char_type;
Chris@16: 
Chris@16:         static typename extract_c_string<T>::char_type const* call (T const str)
Chris@16:         {
Chris@16:             return extract_c_string<T>::call(str);
Chris@16:         }
Chris@16:     };
Chris@16: 
Chris@16:     // Forwarder that strips references
Chris@16:     template <typename T>
Chris@16:     struct extract_c_string<T&>
Chris@16:     {
Chris@16:         typedef typename extract_c_string<T>::char_type char_type;
Chris@16: 
Chris@16:         static typename extract_c_string<T>::char_type const* call (T& str)
Chris@16:         {
Chris@16:             return extract_c_string<T>::call(str);
Chris@16:         }
Chris@16:     };
Chris@16: 
Chris@16:     // Forwarder that strips const references
Chris@16:     template <typename T>
Chris@16:     struct extract_c_string<T const&>
Chris@16:     {
Chris@16:         typedef typename extract_c_string<T>::char_type char_type;
Chris@16: 
Chris@16:         static typename extract_c_string<T>::char_type const* call (T const& str)
Chris@16:         {
Chris@16:             return extract_c_string<T>::call(str);
Chris@16:         }
Chris@16:     };
Chris@16: 
Chris@16:     template <typename T, typename Traits, typename Allocator>
Chris@16:     struct extract_c_string<std::basic_string<T, Traits, Allocator> >
Chris@16:     {
Chris@16:         typedef T char_type;
Chris@16: 
Chris@16:         typedef std::basic_string<T, Traits, Allocator> string;
Chris@16: 
Chris@16:         static T const* call (string const& str)
Chris@16:         {
Chris@16:             return str.c_str();
Chris@16:         }
Chris@16:     };
Chris@16:     
Chris@16:     template <typename T>
Chris@16:     typename extract_c_string<T*>::char_type const*
Chris@16:     get_c_string (T* str)
Chris@16:     {
Chris@16:         return extract_c_string<T*>::call(str);
Chris@16:     }
Chris@16: 
Chris@16:     template <typename T>
Chris@16:     typename extract_c_string<T const*>::char_type const*
Chris@16:     get_c_string (T const* str)
Chris@16:     {
Chris@16:         return extract_c_string<T const*>::call(str);
Chris@16:     }
Chris@16:     
Chris@16:     template <typename String>
Chris@16:     typename extract_c_string<String>::char_type const*
Chris@16:     get_c_string (String& str)
Chris@16:     {
Chris@16:         return extract_c_string<String>::call(str);
Chris@16:     }
Chris@16: 
Chris@16:     template <typename String>
Chris@16:     typename extract_c_string<String>::char_type const*
Chris@16:     get_c_string (String const& str)
Chris@16:     {
Chris@16:         return extract_c_string<String>::call(str);
Chris@16:     }
Chris@16: 
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16:     // Get the begin/end iterators from a string
Chris@16:     ///////////////////////////////////////////////////////////////////////////
Chris@16: 
Chris@16:     // Implementation for C-style strings.
Chris@16: 
Chris@16: // gcc 3.x.x has problems resolving ambiguities here
Chris@16: #if defined(__GNUC__) && (__GNUC__ < 4)
Chris@16:     template <typename T>
Chris@16:     inline typename add_const<T>::type * get_begin(T* str) { return str; }
Chris@16: 
Chris@16:     template <typename T>
Chris@16:     inline typename add_const<T>::type* get_end(T* str)
Chris@16:     {
Chris@16:         T* last = str;
Chris@16:         while (*last)
Chris@16:             last++;
Chris@16:         return last;
Chris@16:     }
Chris@16: #else
Chris@16:     template <typename T>
Chris@16:     inline T const* get_begin(T const* str) { return str; }
Chris@16: 
Chris@16:     template <typename T>
Chris@16:     inline T* get_begin(T* str) { return str; }
Chris@16: 
Chris@16:     template <typename T>
Chris@16:     inline T const* get_end(T const* str)
Chris@16:     {
Chris@16:         T const* last = str;
Chris@16:         while (*last)
Chris@16:             last++;
Chris@16:         return last;
Chris@16:     }
Chris@16: 
Chris@16:     template <typename T>
Chris@16:     inline T* get_end(T* str)
Chris@16:     {
Chris@16:         T* last = str;
Chris@16:         while (*last)
Chris@16:             last++;
Chris@16:         return last;
Chris@16:     }
Chris@16: #endif
Chris@16: 
Chris@16:     // Implementation for containers (includes basic_string).
Chris@16:     template <typename T, typename Str>
Chris@16:     inline typename Str::const_iterator get_begin(Str const& str)
Chris@16:     { return str.begin(); }
Chris@16: 
Chris@16:     template <typename T, typename Str>
Chris@16:     inline typename Str::iterator
Chris@16:     get_begin(Str& str BOOST_PROTO_DISABLE_IF_IS_CONST(Str))
Chris@16:     { return str.begin(); }
Chris@16: 
Chris@16:     template <typename T, typename Str>
Chris@16:     inline typename Str::const_iterator get_end(Str const& str)
Chris@16:     { return str.end(); }
Chris@16: 
Chris@16:     template <typename T, typename Str>
Chris@16:     inline typename Str::iterator
Chris@16:     get_end(Str& str BOOST_PROTO_DISABLE_IF_IS_CONST(Str))
Chris@16:     { return str.end(); }
Chris@16: 
Chris@16:     // Default implementation for other types: try a C-style string
Chris@16:     // conversion.
Chris@16:     // These overloads are explicitly disabled for containers,
Chris@16:     // as they would be ambiguous with the previous ones.
Chris@16:     template <typename T, typename Str>
Chris@16:     inline typename disable_if<is_container<Str>
Chris@16:       , T const*>::type get_begin(Str const& str)
Chris@16:     { return str; }
Chris@16: 
Chris@16:     template <typename T, typename Str>
Chris@16:     inline typename disable_if<is_container<Str>
Chris@16:       , T const*>::type get_end(Str const& str)
Chris@16:     { return get_end(get_begin<T>(str)); }
Chris@16: }
Chris@16: 
Chris@16: namespace result_of
Chris@16: {
Chris@16:     template <typename Char, typename T, typename Enable = void>
Chris@16:     struct get_begin
Chris@16:     {
Chris@16:         typedef typename traits::char_type_of<T>::type char_type;
Chris@16: 
Chris@16:         typedef typename mpl::if_<
Chris@16:             is_const<char_type>
Chris@16:           , char_type const 
Chris@16:           , char_type
Chris@16:         >::type* type;
Chris@16:     };
Chris@16: 
Chris@16:     template <typename Char, typename Str>
Chris@16:     struct get_begin<Char, Str
Chris@16:       , typename enable_if<traits::is_container<Str> >::type>
Chris@16:     {
Chris@16:         typedef typename mpl::if_<
Chris@16:             is_const<Str>
Chris@16:           , typename Str::const_iterator
Chris@16:           , typename Str::iterator
Chris@16:         >::type type;
Chris@16:     };
Chris@16: 
Chris@16:     template <typename Char, typename T>
Chris@16:     struct get_end : get_begin<Char, T> {};
Chris@16: }
Chris@16: 
Chris@16: }}
Chris@16: 
Chris@16: #endif