src/output-impl.lisp: Add a debugging dump of the known constraints.

It's disabled, but the format string is quite hairy, and this rune can
make confusing bugs a little easier to track down so I'm committing it.

diff --git a/src/output-impl.lisp b/src/output-impl.lisp
index d85d77d..96cfa20 100644 (file)
--- a/src/output-impl.lisp
+++ b/src/output-impl.lisp
@@ -62,6 +62,12 @@
     (pushnew function (sequencer-item-functions item))))
 
 (defmethod invoke-sequencer-items ((sequencer sequencer) &rest arguments)
+  #+debug
+  (format *debug-io* "~@<;; ~@;Constraints: ~_~
+                     ~<~@{~<  * ~;~@{~S~^, ~:_~}~:>~:@_~}~:>~:>"
+         (mapcar (lambda (constraint)
+                   (mapcar #'sequencer-item-name constraint))
+                 (sequencer-constraints sequencer)))
   (let ((seen (make-hash-table)))
     (dolist (item (merge-lists (reverse (sequencer-constraints sequencer))))
       (setf (gethash item seen) t)