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Cliff Scott writes:

>In the old days of Image, we used list processing.  We would do a DBGET
>at the begining of the program for each set and then use the previous
>list for later DBGETS.
>
>I was told the other day not to do that because with the large amount of
>memory the 3K has, that I am just wasting CPU time.

The reason to use an item list rather than an @ list has very little to
do with memory. It has a lot more to do with maintainability.

If you use an @ list, you have to recompile every program when you add
items to a dataset, or move them around. If you happen to miss one
program, you get anything from wrong answers to program aborts. By using
a list, you don't have to worry when modifying the data base unless
you're actually changing the size of an item. This seems to be a much
less frequent transformation than adding more items.

In the last few projects I've done, I've enforced a "no @ lists, ever"
rule. The result has been that I can add new functionality very quickly
because almost no old code ever has to be touched.

The extra CPU time is not significant, and using lists is a nice -- and
cheap -- insurance policy. There's not much value in being able to
calculate the wrong answer very quickly.

-- Bruce


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