define-macro.scm 1.3 KB

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  1. ;;; GNU Mes --- Maxwell Equations of Software
  2. ;;; Copyright © 2016,2018 Jan (janneke) Nieuwenhuizen <janneke@gnu.org>
  3. ;;;
  4. ;;; This file is part of GNU Mes.
  5. ;;;
  6. ;;; GNU Mes is free software; you can redistribute it and/or modify it
  7. ;;; under the terms of the GNU General Public License as published by
  8. ;;; the Free Software Foundation; either version 3 of the License, or (at
  9. ;;; your option) any later version.
  10. ;;;
  11. ;;; GNU Mes is distributed in the hope that it will be useful, but
  12. ;;; WITHOUT ANY WARRANTY; without even the implied warranty of
  13. ;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  14. ;;; GNU General Public License for more details.
  15. ;;;
  16. ;;; You should have received a copy of the GNU General Public License
  17. ;;; along with GNU Mes. If not, see <http://www.gnu.org/licenses/>
  18. ;; Setup output file
  19. (set-current-output-port (open-output-file "test/results/test020.answer"))
  20. (define (newline) (display #\newline))
  21. ;; Start with a simple example
  22. (define-macro (foo a) (list 'quote a))
  23. (display (foo bar))
  24. (newline)
  25. ;; Let us make it more complex
  26. (define-macro (bar a) (reverse (list a 'quote)))
  27. (display (bar baz))
  28. (newline)
  29. ;; Let us see if we can add a new primitive
  30. (define-macro (backwards . body)
  31. (cons 'begin
  32. (reverse body)))
  33. ;; now to use it
  34. (backwards
  35. (newline)
  36. (display 3)
  37. (newline)
  38. (display 2)
  39. (newline)
  40. (display 1))
  41. (exit 0)