iterator

from The Free On-line Dictionary of Computing (8 July 2008)

iterator

   <programming> An {object} or {routine} for accessing items
   from a {list}, {array} or {stream} one at a time.

   By extension, the term can be used for an object or routine
   for accesing items from any data structure that can be viewed
   as a list.  For example, a {traverser} is an {iterator} for
   {tree}-shaped data structures.

   (2001-10-04)