;;;; utils.lisp (in-package #:wheelwork) (define-symbol-macro +pi-over-180+ 0.017453292519943295d0) (defun radians (degrees) "Converse DEGREES to radians" (* degrees +pi-over-180+)) (defun safe-slot (object slot &optional default) (if-let (val (and (slot-exists-p object slot) (slot-boundp object slot) (slot-value object slot))) val default))