I'm using Allegro CL 6.0 for Windows.  I'd like to dynamically change
  the availability of menu items in an application I'm building, but I
  can't quite figure out how to do it cleanly.  The way I think it works
  is that if the 'available' slot in a menu item is non-nil, the menu
  item is available, otherwise not.  Is there a way to have a menu item
  test the state of the interface before its menu is displayed, in
  event-driven fashion, or do I need to change the 'available' slot
  explicitly?  Ideally I'd just put a function in the 'available' slot
  to be called at the appropriate time, but that doesn't seem to work.

See the doc page for cg:about-to-show-menu, which is provided for this
purpose.

Ken Cheetham                          <franz.com at cheetham>
Franz Inc.                            Voice: (510) 548-3600 x124
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