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Re: backglue transition

> The move to integrate slapo-glue has had some interesting side effects.
> I'm curious how many of these are intentional and how many of these are
> not:
> 1a. 2.3.0 - 2.3.6 "glue-sub" and such is no longer recognized.
> 1b. of course you get no runtime message about this because no conf
> bailout!

I'll let Howard reply to the rest of your messgae.  Your note about the
bailout suggests me that we could handle this type of transition by
recognizing no longer supported keywords and issue an informative error
message that points the user to more detailed and appropriate info.  This
could be much general (e.g. an API that registers a deprecated statement,
the error message and a clean exit helper, if required).

> 2. The older "subordinate" can be made to work. However, in the past:
> suffix "b,a"
> subordinate
> suffix "c,a"
> subordinate
> suffix "a"
> resulted in { b,a c,a } results.
> The same today results in { c,a b,a } results -- reversed. So if the
> goal was behavior compatibility with earlier versions, we've missed that.

Well, one shouldn't count over the order in which data is returned.

> (Note that 'glue-sub' statements callback the same way as today's
> 'subordinate'. That didn't bother me, though, because it was a new
> syntax.)
> So a few things bother me:
> 1. The slapo-glue config that worked yesterday with 2.3.6 doesn't work--at
> all--today with 2.3.7.
> 2. The config that we tried to be compatible with from, say, 2.2.28
> doesn't work the same way with 2.3.7.
> 3. If I try to use either of those old configs, I get no
> warnings/errors/etc. despite the fact there's a behavior change.
> Finally, although I realize there were reasons for moving things into core
> and making 'subordinate' the keyword, I really liked the slapo-glue
> syntax.

I liked it as well; it made backglue configuration much more compact and
meaningful.  "subordinate" implies that a "superior" will be found at some
point, while glue-sub requires one to know what he's doing.  But having
both is likely to add confusion.


Pierangelo Masarati

    SysNet - via Dossi,8 27100 Pavia Tel: +390382573859 Fax: +390382476497