include/o3tl/enumrange.hxx

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  19
  20 #ifndef INCLUDED_O3TL_ENUMRANGE_HXX
  21 #define INCLUDED_O3TL_ENUMRANGE_HXX
  22
  23 #include <sal/config.h>
  24
  25 namespace o3tl {
  26
  27 ///
  28 /// This is a container convenience class iterating over scoped enumerations.
  29 ///
  30 /// This assumes that the 'enum class' definition
  31 ///  - starts at zero
  32 ///  - has no holes in it's sequence of values
  33 ///  - defines a value called LAST which refers to the greatest constant.
  34 ///
  35 ///  Use like this:
  36 ///     enum class COLOR { RED, GREEN, BLUE, LAST=BLUE };
  37 ///     for( auto e : o3tl::enumrange<Color>() )
  38 ///        .....;
  39 ///
  40 /// \param T the 'enum class' type.
  41 template< typename T>
  42 class enumrange
  43 {
  44 public:
  45     class Iterator
  46     {
  47     public:
  48         Iterator( int value ) :
  49             m_value( value )
  50         {
  51         }
  52
  53         T operator*( void ) const
  54         {
  55             return static_cast<T>(m_value);
  56         }
  57
  58         void operator++( void )
  59         {
  60             ++m_value;
  61         }
  62
  63         bool operator!=( Iterator rhs )
  64         {
  65             return m_value != rhs.m_value;
  66         }
  67
  68     private:
  69         int m_value;
  70    };
  71 };
  72
  73 template< typename T >
  74 typename enumrange<T>::Iterator begin( enumrange<T> )
  75 {
  76     return typename enumrange<T>::Iterator( (int)0 );
  77 }
  78
  79 template< typename T >
  80 typename enumrange<T>::Iterator end( enumrange<T> )
  81 {
  82     return typename enumrange<T>::Iterator( (static_cast<int>(T::LAST)) + 1 );
  83 }
  84
  85 }; // namespace o3tl
  86
  87 #endif /* INCLUDED_O3TL_ENUMRANGE_HXX */
  88
  89 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */