include/o3tl/enumrange.hxx

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  19
  20 #ifndef INCLUDED_O3TL_ENUMRANGE_HXX
  21 #define INCLUDED_O3TL_ENUMRANGE_HXX
  22
  23 namespace o3tl {
  24
  25 ///
  26 /// This is a container convenience class iterating over scoped enumerations.
  27 ///
  28 /// This assumes that the 'enum class' definition
  29 ///  - starts at zero
  30 ///  - has no holes in its sequence of values
  31 ///  - defines a value called LAST which refers to the greatest constant.
  32 ///
  33 ///  Use like this:
  34 ///     enum class COLOR { RED, GREEN, BLUE, LAST=BLUE };
  35 ///     for( auto e : o3tl::enumrange<Color>() )
  36 ///        .....;
  37 ///
  38 /// \param T the 'enum class' type.
  39 template< typename T>
  40 class enumrange
  41 {
  42 public:
  43     class Iterator
  44     {
  45     public:
  46         Iterator( int value ) :
  47             m_value( value )
  48         {
  49         }
  50
  51         T operator*( void ) const
  52         {
  53             return static_cast<T>(m_value);
  54         }
  55
  56         void operator++( void )
  57         {
  58             ++m_value;
  59         }
  60
  61         bool operator!=( Iterator rhs )
  62         {
  63             return m_value != rhs.m_value;
  64         }
  65
  66     private:
  67         int m_value;
  68    };
  69 };
  70
  71 template< typename T >
  72 typename enumrange<T>::Iterator begin( enumrange<T> )
  73 {
  74     return typename enumrange<T>::Iterator( (int)0 );
  75 }
  76
  77 template< typename T >
  78 typename enumrange<T>::Iterator end( enumrange<T> )
  79 {
  80     return typename enumrange<T>::Iterator( (static_cast<int>(T::LAST)) + 1 );
  81 }
  82
  83 }; // namespace o3tl
  84
  85 #endif /* INCLUDED_O3TL_ENUMRANGE_HXX */
  86
  87 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */