RE: MVC in RPG?

-----Original Message-----
On Behalf Of albartell
Could you post an sample of your approach for review? I am curious to
know
how you address partial key chains/setlls/reades/etc, and how you
address
PF's with multiple logicals.


__I didn't do it full-blown but have done a little bit of "offloading"
some I/O to a service program, like for validating screen selections and
other things.

I *think* I like the idea for building new applications or application
"suites" from "scratch", since this would make it easier to do things
with the apps. If not for the limitation of the deadline, for example,
it certainly would have made Y2K a lot easier for a bunch of shops (like
mine).

(And the way some shops did it, 2040 will bring Round 2)

For partial key lists to get at a logical, I just used %parms inside the
procedure to count them and do a select list to separate a CHAIN (or
SETLL) for example.

Select
When %parms >= 3 ;
Chain(e) (key1: key2: key3) OrdFile ;
When %parms >= 2 ;
Chain(e) (key1: key2 ) OrdFile ;
When %parms >= 1 ;
Chain(e) (key1 ) OrdFile ;
When %parms < 1 ;
Read OrdFile ; // (Didn't use this one, but you could...)
EndSL ;

I would suppose you could use %KLST from a DS, and calculate how many
fields from the %parms, but you'd need to load the KLST fields.

You could even set up a STATIC field to track whether it's the first
time in, to determine whether to do a SETLL/READE or just a READE.

I've thought that this might be useful in the stead of using triggers,
IF ->ALL<- your DB access to a file was through this method, because
among other things, it would save the maintenance baggage. That's one
reason they haven't used triggers where I work, where it would
complicate administration for HA with journaling, for example. (Don't
ask; too many files, libraries, environments, etc).

--Alan