srfi-16.scm 1.8 KB

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  1. ;;; srfi-16.scm --- case-lambda
  2. ;; Copyright (C) 2001, 2002, 2006, 2009, 2014 Free Software Foundation, Inc.
  3. ;;
  4. ;; This library is free software; you can redistribute it and/or
  5. ;; modify it under the terms of the GNU Lesser General Public
  6. ;; License as published by the Free Software Foundation; either
  7. ;; version 3 of the License, or (at your option) any later version.
  8. ;;
  9. ;; This library is distributed in the hope that it will be useful,
  10. ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  11. ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12. ;; Lesser General Public License for more details.
  13. ;;
  14. ;; You should have received a copy of the GNU Lesser General Public
  15. ;; License along with this library; if not, write to the Free Software
  16. ;; Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  17. ;;; Author: Martin Grabmueller
  18. ;;; Commentary:
  19. ;; Implementation of SRFI-16. `case-lambda' is a syntactic form
  20. ;; which permits writing functions acting different according to the
  21. ;; number of arguments passed.
  22. ;;
  23. ;; The syntax of the `case-lambda' form is defined in the following
  24. ;; EBNF grammar.
  25. ;;
  26. ;; <case-lambda>
  27. ;; --> (case-lambda <case-lambda-clause>)
  28. ;; <case-lambda-clause>
  29. ;; --> (<signature> <definition-or-command>*)
  30. ;; <signature>
  31. ;; --> (<identifier>*)
  32. ;; | (<identifier>* . <identifier>)
  33. ;; | <identifier>
  34. ;;
  35. ;; The value returned by a `case-lambda' form is a procedure which
  36. ;; matches the number of actual arguments against the signatures in
  37. ;; the various clauses, in order. The first matching clause is
  38. ;; selected, the corresponding values from the actual parameter list
  39. ;; are bound to the variable names in the clauses and the body of the
  40. ;; clause is evaluated.
  41. ;;; Code:
  42. (define-module (srfi srfi-16)
  43. #:re-export (case-lambda))
  44. ;; Case-lambda is now provided by core psyntax.