prehandler: (was: Locking size and position)

[J. Landman Gay]

DunbarX at aol.com wrote:
> Jacques.
> 
> OK, as mainly a development aid I see all that.
> 
> Rev is far less forgiving about trapping reserved words than you-know-what, 
> so (I think) I cannot write a handler that traps "set", checks to see if my 
> immovable object is in danger, and acts appropriately.

Right. None of the command or function keywords pass through the message 
hierarchy, they go directly to the engine, so you can't intercept. 
That's one of the reasons Rev is so fast.

> There was discussion a while back to have a universal handler trap in the 
> engine, way in the front, that could be analyzed at will. What do you think? 
> Before even the frontscripts, offer a control structure like:
> 
> on preHandler theMessage,paramList
> ...
> end preHandler
> 
> 
> It almost always just passes the usual stuff through, but you could check 
> it at will to see, perhaps, if 'myImmovableObject' was somewhere in the 
> paramList, and catch the "set" message that might be about to change its loc.

I used to be adamant that we needed a feature like that. I changed my 
mind because there was always some other way to do what I needed. Old 
habits die hard, but eventually they do hibernate.

-- 
Jacqueline Landman Gay         |     jacque at hyperactivesw.com
HyperActive Software           |     http://www.hyperactivesw.com