Re: [boost] [serialization]

Robert, Thanks - you hit the nail on the head. I had commented out the mutating value() accessor as a test and forgot to uncomment it... Sorry for the false alarm. Matthias

The error message suggests that we're trying to change the value of a const reference.

does q.value() return a ref to a const?

perhaps instead of serializing q.value() you want to serialize the underlying value directly and making serialization::access a friend of boost::units::quantity<Unit,Y>

Robert Ramey