chickadee » srfi-158 » gindex

Creates a generator that returns elements of value-gen specified by the indices (non-negative exact integers) generated by index-gen. It is an error if the indices are not strictly increasing. The result generator is exhausted when either generator is exhausted, at which time the other is in an undefined state.

(generator->list (gindex (list->generator '(a b c d e f))
                         (list->generator '(0 2 4))))
  ⇒ (a c e)