cocoa: avoid infinite loop on re-dispatch of command keys

collects/mred/private/wx/cocoa/menu-bar.rkt

@@ -35,6 +35,7 @@
    "MrEd"))
 
 (define the-apple-menu #f)
+(define recurring-for-command (make-parameter #f))
 
 (define-objc-class MyBarMenu NSMenu
   []
@@ -44,13 +45,16 @@
       (or (and the-apple-menu
                (tell #:type _BOOL the-apple-menu performKeyEquivalent: evt))
           ;; Explicity send the event to the keyWindow:
+          (and
+           (not (recurring-for-command))
            (let ([w (tell app keyWindow)])
              (and w
                   (let ([r (tell w firstResponder)])
                     (and r
                          (begin
-                          (tell r keyDown: evt)
-                          #t))))))))
+                           (parameterize ([recurring-for-command #t])
+                             (tell r keyDown: evt))
+                           #t)))))))))
 
 (define cocoa-mb (tell (tell MyBarMenu alloc) init))
 (define current-mb #f)