boostorg/detail
1
0
Fork 1
mirror of https://github.com/boostorg/detail.git synced 2025-08-05 15:24:26 +02:00
Code Issues Packages Projects Releases Wiki Activity

move to namespace detail

Browse Source 
[SVN r36027]
This commit is contained in:
Beman Dawes
2006-11-13 22:10:57 +00:00
parent a548ecc968
commit 87ff652a07
1 changed files with 57 additions and 54 deletions
Download Patch File Download Diff File Expand all files Collapse all files

111
include/boost/detail/identifier.hpp
View File

@@ -16,71 +16,74 @@
namespace boost namespace boost
{ {
// class template identifier ---------------------------------------------// namespace detail
// Always used as a base class so that different instantiations result in
// different class types even if instantiated with the same value type T.
// Expected usage is that T is often an integer type, best passed by
// value. There is no reason why T can't be a possibly larger class such as
// std::string, best passed by const reference.
// This implementation uses pass by value, based on expected common uses.
template <typename T, typename D>
class identifier
{ {
public: // class template identifier ---------------------------------------------//
typedef T value_type;
const value_type value() const { return m_value; } // Always used as a base class so that different instantiations result in
void assign( value_type v ) { m_value = v; } // different class types even if instantiated with the same value type T.
bool operator==( const D & rhs ) const { return m_value == rhs.m_value; } // Expected usage is that T is often an integer type, best passed by
bool operator!=( const D & rhs ) const { return m_value != rhs.m_value; } // value. There is no reason why T can't be a possibly larger class such as
bool operator< ( const D & rhs ) const { return m_value < rhs.m_value; } // std::string, best passed by const reference.
bool operator<=( const D & rhs ) const { return m_value <= rhs.m_value; }
bool operator> ( const D & rhs ) const { return m_value > rhs.m_value; }
bool operator>=( const D & rhs ) const { return m_value >= rhs.m_value; }
typedef void (*unspecified_bool_type)(D); // without the D, unspecified_bool_type // This implementation uses pass by value, based on expected common uses.
static void unspecified_bool_true(D){} // conversion allows relational operators
// between different identifier types
operator unspecified_bool_type() const { return m_value == value_type() ? 0 : unspecified_bool_true; } template <typename T, typename D>
bool operator!() const { return m_value == value_type(); } class identifier
{
public:
typedef T value_type;
// constructors are protected so that class can only be used as a base class const value_type value() const { return m_value; }
protected: void assign( value_type v ) { m_value = v; }
identifier() {}
explicit identifier( value_type v ) : m_value(v) {}
#if !defined(BOOST_MSVC) || BOOST_MSVC > 1300 // 1300 == VC++ 7.0 bug workaround bool operator==( const D & rhs ) const { return m_value == rhs.m_value; }
private: bool operator!=( const D & rhs ) const { return m_value != rhs.m_value; }
#endif bool operator< ( const D & rhs ) const { return m_value < rhs.m_value; }
T m_value; bool operator<=( const D & rhs ) const { return m_value <= rhs.m_value; }
}; bool operator> ( const D & rhs ) const { return m_value > rhs.m_value; }
bool operator>=( const D & rhs ) const { return m_value >= rhs.m_value; }
#ifndef BOOST_NO_SFINAE typedef void (*unspecified_bool_type)(D); // without the D, unspecified_bool_type
static void unspecified_bool_true(D){} // conversion allows relational operators
// between different identifier types
template <class Ostream, class Id> operator unspecified_bool_type() const { return m_value == value_type() ? 0 : unspecified_bool_true; }
typename enable_if< is_base_of< identifier< typename Id::value_type, Id >, Id >, bool operator!() const { return m_value == value_type(); }
Ostream & >::type operator<<( Ostream & os, const Id & id )
{
return os << id.value();
}
template <class Istream, class Id> // constructors are protected so that class can only be used as a base class
typename enable_if< is_base_of< identifier< typename Id::value_type, Id >, Id >, protected:
Istream & >::type operator>>( Istream & is, Id & id ) identifier() {}
{ explicit identifier( value_type v ) : m_value(v) {}
typename Id::value_type v;
is >> v;
id.value( v );
return is;
}
#endif
#if !defined(BOOST_MSVC) || BOOST_MSVC > 1300 // 1300 == VC++ 7.0 bug workaround
private:
#endif
T m_value;
};
//#ifndef BOOST_NO_SFINAE
// template <class Ostream, class Id>
// typename enable_if< is_base_of< identifier< typename Id::value_type, Id >, Id >,
// Ostream & >::type operator<<( Ostream & os, const Id & id )
// {
// return os << id.value();
// }
// template <class Istream, class Id>
// typename enable_if< is_base_of< identifier< typename Id::value_type, Id >, Id >,
// Istream & >::type operator>>( Istream & is, Id & id )
// {
// typename Id::value_type v;
// is >> v;
// id.value( v );
// return is;
// }
//#endif
} // namespace detail
} // namespace boost } // namespace boost
#endif // BOOST_IDENTIFIER_HPP #endif // BOOST_IDENTIFIER_HPP