Re: variable exchange

Patricia Shanahan wrote:
I've known the technique for about 20 years. I have yet to encounter a
situation in which I've needed to use it.

I think I used it once. In Z80 assembler. There, and maybe in the IOCCC it might have its place.

Oh, and a variant is useful in interactive computer graphics. To draw a cursor on top of some graphics and to erase the cursor later, without having to remember the graphics contents under the cursor.

/Thomas
--
The comp.lang.java.gui FAQ:
http://gd.tuwien.ac.at/faqs/faqs-hierarchy/comp/comp.lang.java.gui/
ftp://ftp.cs.uu.nl/pub/NEWS.ANSWERS/computer-lang/java/gui/faq
.

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