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> From: Jay Weedon [mailto:jweedon@EARTHLINK.NET]
>
> Sorry to display such ignorance. Can someone point me to an explanation of
what this term means
> & what it's used for?
Jay,
It has nothing to do with the ignorance: the DOW-loop is not a standard
industry term :-). Rather, it is an abbreviation that has become quite
common on SAS-L in the last year or so. A while ago, Ian Whitlock,
responding to a SAS-L inquiry, casually used a DO-loop in a certain peculiar
manner, which one of us (apparently not exceedingly bright) failed to fully
comprehend at once. However, the more he thought about it, the more he
realized the potential hidden in such a structure, and eventually started
using it on SAS-L and his own work here, and there, and everywhere, which
led to an even better understanding on his part, plus it gave birth to
certain tricks he has added himself thereafter. First, he (and others)
called it plainly "Whitlock DO-loop", but it seemed to be in need of an
easily digested abbreviation. He threw several variants in SAS-L, the group,
but the group chewed ont he nibble for a while, but never really got it.
Then he thought of "WDO-loop"; however, since "WDO" may also stand for 'wood
destroying organism', its foremost connotation with programming would be 'a
bug'. However, DOW-loop, even though it too stands for something known else,
turned out to be a good bait, and began to spread. This is as far as the
semantics is concerned, and that is where it is now.
As far as the substance goes, the only piece of "documentation" I have seen
(other than a part of my forthcoming SESUG paper "The Magnificent DO") is a
piece I %include in each program where I use the construct, since whoever is
a poor chap that might inherit the code, he (1) not guaranteed to be an avid
sas-l reader, (2) let alone be able to delve into Ian's coding maneuvers
without a dramatic increase of his own CPU container's angular momentum. I
would post that disclaimer, but since David Cassell has already did it
(thanks!), I can rest.
Kind regards,
=================
Paul M. Dorfman
Jacksonville, FL
=================
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