libiterator-util-perl 0.02+ds1-1 (i386 binary) in ubuntu xenial

 Iterator::Util implements many useful functions for creating and manipulating
 iterator objects.
 .
 An "iterator" is an object, represented as a code block that generates the
 "next value" of a sequence, and generally implemented as a closure. For
 further information, including a tutorial on using iterator objects, see the
 Iterator documentation.