chickadee » srfi-196 » range-filter-map->list

Applies proc element-wise to the elements of the ranges and returns a range/list of the true values returned by proc. If more than one range is given and not all ranges have the same length, these procedures terminate when the shortest range is exhausted. The dynamic order in which proc is actually applied to the elements is unspecified. The range-filter-map procedure eagerly computes its result and returns an expanded range. The runtime of these procedures is O(n) where n is the sum of the total accessing times of the ranges.

Examples:

(range->list (range-filter-map (lambda (x) (and (even? x) (* x x)))
                               (numeric-range 0 10)))
  ⇒ (0 4 16 36 64)

(range-filter-map->list (lambda (x y)
                          (and (< x y) (* x y)))
                        (numeric-range 0 10 2)
                        (numeric-range 5 15))
  ⇒ (0 12 28 48 72)