tail recursion
 n.

    If you aren't sick of it already, see tail recursion.

	

	tail recursion

    When the last thing a function (or procedure)
   does is to call itself.  Such a function is called tail
   recursive.  A function may make several recursive calls but
   a call is only tail-recursive if the caller returns
   immediately after it.  E.g.

   	f n = if n < 2 then 1 else f (f (n-2) + 1)

   In this example both calls to f are recursive but only the
   outer one is tail recursive.

   Tail recursion is a useful property because it enables tail
   recursion optimisation.

   If you aren't sick of them already, see recursion and tail
   recursion.

   [Jargon File]

   (2006-04-16)