Re: [boost] [Boost Review] Property Tree Library --canaboost::serialization expert assess interfacing options

From: Robert Ramey (ramey_at_[hidden])
Date: 2006-04-23 12:19:54

Jeff Garland wrote:
> On Sun, 23 Apr 2006 11:01:10 -0400, Eugene Talagrand wrote
>
>> Just a note, type tracking can be disabled in the case you described
>> and version tags can be disabled in general. In this case, hand-
>> editing becomes feasible: boost::serialization XML archives are what
>> I currently use for config files, though my needs may be more
>> limited than most. You're right that the order of fields matters in
>> boost::serialization, but the order of tags does matter in XML in
>> general.
>
> Well, the order of fields only matters in boost::serialization
> because all the current archive classes read in order from the
> serialized data.

I did it this way for two reasons:
a) it was easier
b) it supports arbitrary sized archives - they don't have to be loaded
all into memory.

>I assure you that a serialization archive can be
> built that doesn't depend directly on order.  Essentially the archive
> would read and parse the data into an intermediate structure
> (property tree might be good :-) and then responds to the
> deserialization requests using a mapped based lookup instead of
> getting the next data from the file.

I'm surprised that no one (that I know of) hasn't done this.

> The same exact implementation
> can be used to make a binding to a database buffer derived from an
> sql command -- this also might not have the fields in the same order
> as the object being serialized.

>Not providing support for this case
> was one of the reasons that boost::serialization was orginally
> rejected.

Hmm it still doesn't permit re-ordering of the data items at any level - 
still
it got accepted. Maybe I just outlasted my critics.

Robert Ramey