caption                                        (Assignable)

        Contains either a text string that concisely describes the menu
        option or a menu separator specifier.  MenuItem:caption is the text
        that appears in the actual menu.

        A menu separator is a horizontal line in a pop-up menu that separates
        menu items into logical groups.  Use the constant MENU_SEPARATOR in
        Button.ch to assign the menu separator specifier to MenuItem:caption.

        When present, the & character specifies that the character
        immediately following it in the caption is the menu item's
        accelerator key.  The accelerator key provides a quick and convenient
        mechanism for the user to select a menu item when the menu that it is
        contained within has input focus.  When the menu is a member of a
        TopBarMenu object, the user selects the menu item by pressing the Alt
        key in combination with the accelerator key.  When the menu is a
        member of a PopUpMenu object, the user selects the menu item by
        simply pressing the accelerator key.  The accelerator key is not case
        sensitive.