Well behaved post_eval_functions list (finally)

--- Wolfgang Jenkner  wrote:
> C Y  writes:
> 
> > Hmm.  Re-reading that, I'm sorry if I came off as too aggressive.
> 
> I didn't explain why I wanted the changes, so, in a sense, I passed
> the borderline between proposing a point of view and trying to impose
> it.  I am sorry about that.

No worries. :-).

> I simply thought that a more modular set-up would be a quick way to
> settle things such that 
> (1) you could continue your work at the `units' and 
>`post_eval_functions' packages, 

That should be OK actually - for testing purposes it's usually better
to manually run processunits.  The main use of post_eval_functions
would be at a user level.

> (2) interested people could use them, 

Heh - at this stage, it's probably a good thing there are a few hoops
to jump through to get it to work, really.

> (3) my sense of aesthetics would be pleased, 

Not a bad reason, actually - I think good coding and aesthetics are
somehow fundamentally mixed up :-)  I worry a little about encouraging
packages to monkey with defining their own toplevel eval command -
Barton and I (well moreso with Barton because he's smarter :-P) were
sweating bullets about changing it even once.  We were trying to come
up with a mechanism that was harmless by default, and would provide one
(and only one) well defined way to change this behavior so problems
stemming from functions added to the list would be at least somewhat
easier to track down.  

> (4) the (IMHO) misguided use of `kill' would be obviated, 

This is the one where I have to disagree - I keep finding myself even
in testing typing kill(post_eval_functions), and I ought to know
better.  Even more so in the kill(all) case - I would expect that to
get rid of any inconvenient lurkers in post_eval_functions. Maybe this
is just the end user in me being unreasonable?

> (5) nobody had to worry about the impact on (the coming release of) 
> Maxima (not that I see a serious problem here).

If somebody is leery about post_eval_functions it can wait - it is a
rather sensitive area in Maxima to be making changes.  Once I get off
my rear and impliment the convert function the unit package will be
useful without needing the automatic running of processunits (and in
any case that can already be done by hand.)  I don't really have my
heart set on having the units package functional by 5.9.2, since there
is quite a bit more work to do on it before I'll be satisfied with it
anyway.

Cheers,
CY

__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com