Re: MVC in RPG?

[Jerry Adams <jerry@xxxxxxxxxxxxxxx>]

Lim Hock-Chai wrote:
> 4.  Why replace RPG io functions that all RPG developers are familiar with with your own io
> functions that no new comer can understand without additional trainings?
>   
I've been following this discussion with some interest.  Paul Tuohy gave 
an excellent session on externalizing (abstracting) db access at COMMON, 
and I think he's giving it at the System i Developer conference (oops, 
that starts today, what am I doing here?). 

Your other objections may or may not have merit, Lim.  I'll leave that 
for more experienced people than I.  However, the objection (above) 
doesn't hold water.  The abstraction is a service program.  Whether the 
function of a service program is to calculate various bank rates or to 
do data abstractions, it is not necessary to know how the service 
program works: "Here it is, this is what it returns, and no you don't 
need to know how it works."

The same objection  could be made about any new feature in the language 
itself, such as subprocedures or BIF's.  In fact, think of the data 
abstraction as a BIF because that's exactly what it would be.  You and I 
have absolutely no need to know how the %found() bif works; it just does.

	* Jerry C. Adams
*IBM System i Programmer/Analyst
B&W Wholesale Distributors, Inc.* *
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