Method computeDistance

external/jsoncpp/jsoncpp.cpp:1274–1308

ValueIteratorBase::difference_type 
ValueIteratorBase::computeDistance( const SelfType &other ) const
{
#ifndef JSON_VALUE_USE_INTERNAL_MAP
# ifdef JSON_USE_CPPTL_SMALLMAP
   return current_ - other.current_;
# else
   // Iterator for null value are initialized using the default
   // constructor, which initialize current_ to the default
   // std::map::iterator. As begin() and end() are two instance 
   // of the default std::map::iterator, they can not be compared.
   // To allow this, we handle this comparison specifically.
   if ( isNull_  &&  other.isNull_ )
   {
      return 0;
   }


   // Usage of std::distance is not portable (does not compile with Sun Studio 12 RogueWave STL,
   // which is the one used by default).
   // Using a portable hand-made version for non random iterator instead:
   //   return difference_type( std::distance( current_, other.current_ ) );
   difference_type myDistance = 0;
   for ( Value::ObjectValues::iterator it = current_; it != other.current_; ++it )
   {
      ++myDistance;
   }
   return myDistance;
# endif
#else
   if ( isArray_ )
      return ValueInternalArray::distance( iterator_.array_, other.iterator_.array_ );
   return ValueInternalMap::distance( iterator_.map_, other.iterator_.map_ );
#endif
}


bool