RE: Activation Groups & File Overrides

Jon Erickson wrote:

> I'm attempting to separate a common subroutine into its own module, (MOD1)
> to be bound and callable from other programs/modules.
> 
> The Module opens File1 for input.  I'd like to be able to call this module
> repeatably without the file initialization overhead, yet not have to call
> the module an additional time just to seton LR to close the file. 
> 
> Any insight appreciated..

Is there a specific reason you decided against the extra call to close the
file?  It seems to me that if the decision to close the file is made by
MOD1's caller(s) then the caller(s) will need to know internal details of
how MOD1 works (did MOD1 open the file successfully?)

Moving closer to Utopia, MOD1 should have at least 3 procedures that are
Public: Open, OperateOnFILE1Data, Close.  That way you can bundle the data
and the code needed to manipulate it all in one place.  The ideal
environment would have a separate procedure for each operation you need
performed on FILE1's data: Read, Write, Update, Position, etc. instead of a
global OperateOnFILE1Data.  This way, each procedure does one thing and one
thing well.  

Not all of these procedures need to be public: if you need to total up the
A/R for an account, you may have a public GetTotalAR(CustomerID: ARTotal)
that calls the internal Read procedure.  This way you can separate the
actual I/O from the processing.  If you decide to use ODBC or SQL tomorrow,
you just change the I/O procedure and the rest of MOD1 is ready "as-is."  

That's my insight anyway.  And it's worth every penny you paid for it!  :-)

Buck Calabro
Aptis, Albany, NY
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