install an error handler for the execution of commands.

scheme/nuit-engine.scm

@@ -175,6 +175,9 @@
       standard-command-plugin))
 
 (define (eval-command-in-command-mode command-line)
+  (with-fatal-error-handler*
+   display-error-and-continue
+   (lambda ()
      (let* ((tokens (split-command-line command-line))
 	    (command (car tokens))
 	    (args (cdr tokens))
@@ -195,7 +198,7 @@
        (refresh-result-window)
        (move-cursor (command-buffer) (result-buffer))
        (refresh-command-window)
-    (release-lock paint-lock)))
+       (release-lock paint-lock)))))
 
 (define (display-error-and-continue condition more)
   (let ((win (app-window-curses-win (result-window))))