diff options
Diffstat (limited to 'lisp/emacs-lisp/cl-print.el')
| -rw-r--r-- | lisp/emacs-lisp/cl-print.el | 35 |
1 files changed, 24 insertions, 11 deletions
diff --git a/lisp/emacs-lisp/cl-print.el b/lisp/emacs-lisp/cl-print.el index 65c86d2b65e..70ccaac17b3 100644 --- a/lisp/emacs-lisp/cl-print.el +++ b/lisp/emacs-lisp/cl-print.el @@ -37,6 +37,7 @@ "If non-nil, try and make sure the result can be `read'.") (defvar cl-print--number-table nil) +(defvar cl-print--currently-printing nil) ;;;###autoload (cl-defgeneric cl-print-object (object stream) @@ -59,8 +60,9 @@ call other entry points instead, such as `cl-prin1'." (princ "(" stream) (cl-print-object car stream) (while (and (consp object) - (not (and cl-print--number-table - (numberp (gethash object cl-print--number-table))))) + (not (if cl-print--number-table + (numberp (gethash object cl-print--number-table)) + (memq object cl-print--currently-printing)))) (princ " " stream) (cl-print-object (pop object) stream)) (when object @@ -156,15 +158,26 @@ call other entry points instead, such as `cl-prin1'." (cl-defmethod cl-print-object :around (object stream) ;; FIXME: Only put such an :around method on types where it's relevant. - (let ((n (if cl-print--number-table (gethash object cl-print--number-table)))) - (if (not (numberp n)) - (cl-call-next-method) - (if (> n 0) - ;; Already printed. Just print a reference. - (progn (princ "#" stream) (princ n stream) (princ "#" stream)) - (puthash object (- n) cl-print--number-table) - (princ "#" stream) (princ (- n) stream) (princ "=" stream) - (cl-call-next-method))))) + (cond + (print-circle + (let ((n (gethash object cl-print--number-table))) + (if (not (numberp n)) + (cl-call-next-method) + (if (> n 0) + ;; Already printed. Just print a reference. + (progn (princ "#" stream) (princ n stream) (princ "#" stream)) + (puthash object (- n) cl-print--number-table) + (princ "#" stream) (princ (- n) stream) (princ "=" stream) + (cl-call-next-method))))) + ((let ((already-printing (memq object cl-print--currently-printing))) + (when already-printing + ;; Currently printing, just print reference to avoid endless + ;; recursion. + (princ "#" stream) + (princ (length (cdr already-printing)) stream)))) + (t (let ((cl-print--currently-printing + (cons object cl-print--currently-printing))) + (cl-call-next-method))))) (defvar cl-print--number-index nil) |