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Tilde Newline: Ignored Newline

Tilde immediately followed by a newline ignores the newline and any following non-newline whitespace_1 characters. With a :, the newline is ignored, but any following whitespace_1 is left in place. With an @, the newline is left in place, but any following whitespace_1 is ignored. For example:

      (defun type-clash-error (fn nargs argnum right-type wrong-type)
        (format *error-output*
                "~&~S requires its ~:[~:R~;~*~]~
                argument to be of type ~S,~
                with an argument of type ~S.~
                fn (eql nargs 1) argnum right-type wrong-type))
      (type-clash-error 'aref nil 2 'integer 'vector)  prints:
     AREF requires its second argument to be of type INTEGER,
     but it was called with an argument of type VECTOR.
     NIL
      (type-clash-error 'car 1 1 'list 'short-float)  prints:
     CAR requires its argument to be of type LIST,
     but it was called with an argument of type SHORT-FLOAT.
     NIL
     

Note that in this example newlines appear in the output only as specified by the ~& and ~% directives; the actual newline characters in the control string are suppressed because each is preceded by a tilde.