[boost] [serialization] Specification of different class version on transmit

From: John Haller (jhaller_at_[hidden])
Date: 2006-06-28 09:39:58

Has there been consideration to supporting setting
the class version on output?  This is useful when
transmitting classes over a network without requiring
both sides to be at the same software version.  While
the current version support allows the newer side
to interpret an older message format, there is no
way for the newer side to use the older serialization.
This requires an immediate transition of all communicating
parties to a common version, which is unreasonable
in a heterogeneous network.

Implementation probably has a number of issues, as
there could be multiple connections, each with its
own ideas of supported versions for each class.
How the two sides agree on a class version is
outside the scope of serialization, although
a companion framework may be suitable.  But
support for specification of version information
for use by transmit serialization is required
to be able to write such a companion class.
There may also need to be some support in the
archive templates to associate a particular class
with a particular output version.