examples/ex-100.rkt
#lang racket
(require (planet wcy/mpost-wrapper))
(provide main)
(define (main)
  (let* ((origin (point 0 0))
         (A (point '2cm '2cm)))
    (for ((i (in-range 4)))
         (drawarrow (rotate (op* (* i -1/3) (op-angle A))
                            (op-- origin A))))))