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Diffstat (limited to 'hyperquirks.lisp')
-rw-r--r-- | hyperquirks.lisp | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/hyperquirks.lisp b/hyperquirks.lisp index b399519..2c7de1a 100644 --- a/hyperquirks.lisp +++ b/hyperquirks.lisp @@ -181,6 +181,27 @@ And would return +(defmacro defun-case (name &rest clauses) + "Clauses look like (VARLIST . BODY) + +E.g. + +(defun-case foobar + (() 10) + ((x y) (+ x y)) + ((foo) (* foo 2)) + ((a b c d) (list a b c d)))" + (let* ((rest-args + (gensym "variable-pattern-")) + (clauses + (loop for (arglist . body) in clauses + collect `(,(length arglist) + (destructuring-bind ,arglist ,rest-args + ,@body))))) + `(defun ,name (&rest ,rest-args) + (case (length ,rest-args) + ,@clauses)))) + ;;; LIST FUNCTIONS (defun group (n xs &optional default) |