Re: [office] Conformance Clause proposal, Version 8

[Andreas J Guelzow <aguelzow@math.concordia.ab.ca>]

On Sat, 2009-02-07 at 00:54 +0000, Bob Jolliffe wrote:
> The current proposal regarding prefixes in table:formula seems to
> quite clearly not allow extensions in conforming documents.   For a
> conforming document this is as it should be, to avoid incompatibility
> between spreadsheet applications.

I really see no chance of avoiding incompatibilities between spreadsheet
applications, considering the current draft of OpenFormula. Some (many?)
functions contain "implementation defined" results for at least some
possible arguments. Unless there is some verification mechanism to
ensure that those argument values cannot occur, the standard cannot
expect interoperability for conformant spreadsheet applications.

For example VLOOKUP a function in the "small" and so required by
virtually any implementation may expect the DataSource (one of its
arguments) to be sorted. But the sort order required may depend on
whether the application implements a separate "logical" type. If
DataSource is not sorted, the result is undetermined and
implementation-dependent. Since the same DataSource may be sorted for
one application and not another, I am not sure how one could expect
interoperability.  

Andreas

-- 
Andreas J. Guelzow
Concordia University College of Alberta