Re: RFC: goals for rewritten output subsystem

[Jason Stover]

On Fri, May 30, 2008 at 08:00:42PM +0100, Ed wrote:
> 2008/5/30 Ben Pfaff <address@hidden>:
> > 2. Problem: PSPP output is not easily machine-readable in a
> >   semantically meaningful way.  That is, data produced as part
> >   of the output is difficult to extract for use by other
> >   software or by subsequent PSPP procedures.  Another aspect of
> >   the same issue is that PSPP tests that compare output end up
> >   compare cosmetic details of the formatting, not just the data
> >   produced.
> >
> >   Goal: The new output subsystem should be able to produce
> >   machine-readable, semantically meaningful data output in at
> >   least one widely understood format, such as CSV or an XML
> >   schema.  Then tests can compare this output format.
> 
> There seems to me to be a disconnect here between the problem and the
> goal as stated. The problem that "output is difficult to extract for
> use by ... subsequent PSPP procedures" is not addressed specifically
> (unless the argument is that parsing XML or CSV back into memory is
> the only solution for this - various in-memory options seem naively
> viable too, and to offer much better performance, and are perhaps less
> cumbersome for the user..)

I don't think this must be the place to mention the details, just to
broadly define a few goals. It may be that some kinds of output should
be structs in memory, meant to be used within PSPP, and some output
should go elsewhere (CSV or XML, etc.). But as stated, the goal leaves
room for all that. It does say "at least one widely understood format", so
we could have two or more. 

To implement this, we might have to categorize different types of
output, but that is a problem of implementing the goal, rather than
the goal itself.

-Jason