diff options
| -rw-r--r-- | emacs/.emacs.d/wpc/cycle.el | 28 |
1 files changed, 19 insertions, 9 deletions
diff --git a/emacs/.emacs.d/wpc/cycle.el b/emacs/.emacs.d/wpc/cycle.el index 9475ddd99659..592de10e0de7 100644 --- a/emacs/.emacs.d/wpc/cycle.el +++ b/emacs/.emacs.d/wpc/cycle.el @@ -34,17 +34,19 @@ (defconst cycle/enable-tests? t "When t, run the tests defined herein.") -(defun cycle/new (&rest xs) - "Create an empty cycle." - (make-cycle :current-index 0 - :previous-index nil - :xs xs)) - (defun cycle/from-list (xs) "Create a cycle from a list of `XS'." - (make-cycle :current-index 0 - :previous-index nil - :xs xs)) + (if (= 0 (length xs)) + (make-cycle :current-index nil + :previous-index nil + :xs xs) + (make-cycle :current-index 0 + :previous-index nil + :xs xs))) + +(defun cycle/new (&rest xs) + "Create a cycle with XS as the values." + (cycle/from-list xs)) (defun cycle/to-list (xs) "Return the list representation of a cycle, XS." @@ -135,6 +137,14 @@ underlying struct." cycle-xs (list/contains? x))) +(defun cycle/empty? (xs) + "Return t if cycle XS has no elements." + (= 0 (length (cycle-xs xs)))) + +(defun cycle/focused? (xs) + "Return t if cycle XS has a non-nil value for current-index." + (maybe/some? (cycle-current-index xs))) + ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Tests ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; |