MENU is a specifier for a menu. For the simplest case, MENU is a keymap.
The menu items come from key bindings that have a menu string as well as
a definition; actually, the "definition" in such a key binding looks like
-\(STRING . REAL-DEFINITION). To give the menu a title, put a string into
+(STRING . REAL-DEFINITION). To give the menu a title, put a string into
the keymap as a top-level element.
If REAL-DEFINITION is nil, that puts a nonselectable string in the menu.
An ITEM may also be just a string--that makes a nonselectable item.
An ITEM may also be nil--that means to put all preceding items
on the left of the dialog box and all following items on the right.
-\(By default, approximately half appear on each side.)
+(By default, approximately half appear on each side.)
If HEADER is non-nil, the frame title for the box is "Information",
otherwise it is "Question".