examples/ex-102.rkt
#lang racket
(require (planet wcy/mpost-wrapper))
(require (planet wcy/mpost-wrapper/label))
(provide main)
(define (main)
  (let* ((A (point 0 0))
         (B (point '3cm 0))
         (C (point '1cm '2cm)))
    (draw (op-- A B C 'cycle))
    (label-llft (TEX (decimal (op- (op-angle (op- C A))
                                   (op-angle (op- B A))))) A)
    (label-lrt (TEX (decimal (op- (op-angle (op- A B))
                                  (op-angle (op- C B))))) B)
    (label-urt (TEX (decimal (op- (op-angle (op- B C))
                                  (op-angle (op- A C))))) C)
    ))