fix: org tangle — fix END_SRC boundaries in mouse.org/slot.org (prose inside code blocks), replace emacs tangle with Python script that handles all blocks

org/slot.org

@@ -51,11 +51,26 @@ Slot modes:
         (setf (gethash key *slots*)
               (sort (cons (cons order render-fn) entries) #'< :key #'car))))
   render-fn)
+#+END_SRC
 
+*** Bug Fixes (v1.0.0): nil handler guard in slot-render
+
+~slot-render~ called ~(apply (cdr entry) args)~ unconditionally, but
+~defslot~ stores ~(order . render-fn)~ pairs where ~render-fn~ can be
+~nil~ (if called without ~:render-fn~).  This caused a type error when
+~apply~ received ~nil~ as the function argument.
+
+Fix: Check ~(when fn)~ before calling ~apply~.  Entries with a nil
+handler are silently skipped.
+
+#+BEGIN_SRC lisp :tangle ../src/components/slot.lisp :noweb no
 (defun slot-render (slot-name &rest args)
   (let ((entries (gethash (string slot-name) *slots*)))
     (when entries
-      (mapcar (lambda (entry) (apply (cdr entry) args)) entries))))
+      (mapcar (lambda (entry)
+                (let ((fn (cdr entry)))
+                  (when fn (apply fn args))))
+              entries))))
 
 (defun slot-p (slot-name)
   (nth-value 1 (gethash (string slot-name) *slots*)))