template< class T> T::value_type operator[]( TypedField< T > const& f) const;
Return the value of a field as boost::optional.
template< class T> boost::optional< std::decay_t< typename T::value_type > > operator[]( OptionaledField< T > const& of) const;
Return a modifiable field value.
template< class T> ValueProxy< T > operator[]( TypedField< T > const& f);
Return a modifiable field value as boost::optional.
template< class T> OptionalProxy< T > operator[]( OptionaledField< T > const& of); template< class T> auto operator[]( TypedField< T > const& f); template< class T> auto operator[]( OptionaledField< T > const& of);