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Message1. <> comparison is always false
#12527
Posted by: Michael S 2008-11-27 17:53:50 Last edited by: Jeff Glatt 2009-03-04 14:06:41 (Total edited 1 time)
Run the following:
y = '          '
DO WHILE y <> ''
	y = STRIP(y)
END
SAY 'Finished'	
The loop ends immediately (ie, not even one iteration).
Message2.
#12530
Posted by: Jeff Glatt 2008-11-28 01:47:39
The comparison operator <> is not a strict operator. That means, it trims leading and trailing spaces off the strings before doing the comparison. So if you take a string that is all spaces, it gets trimmed down to an empty string. And of course, the two empty strings are equal.

If leading/trailing spaces are important, then use a strict operator such as \==.
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