[Sorry, English only.]

Good afternoon.
	I need a double-ended queue implementation. The lists
can get very long, so I would like to use imperative operations to
change the links.

	I've tried all the naïve type declarations --- all of which
don't seem to work.  I've tried the age old tricks. What am I not
understanding? or doing right? I'm not fussy: tuples, records or
objects are fine.

Best regards,

steve
-----
Steve (really "D. E.") Stevenson           Assoc Prof
Department of Computer Science, Clemson,   (864)656-5880.mabell
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