|virtual base::DataSourceBase *||build (const std::string &op, base::DataSourceBase *a)=0|
UnaryOperator contains information on some unary operator that operates on one arg of a certain type. Examples of unary operators are logical not for booleans, unary minus for ints, unary minus for doubles, unary minus for vectors, unary plus for ints (internal::identity operator) etc. We always provide templates that accept a STL style adaptable functor..
If op is the operator you are responsible for, and if the argument internal::DataSource is of the correct type, then return an appropriate DataSource. ( i.e. a internal::DataSource that will apply a certain operation on the value it gets from its argument internal::DataSource, and will return that value ). Otherwise, return 0.
Implemented in RTT::types::UnaryOperator< function >.