GNU Emacs Lisp Reference Manual

1.3.6: Buffer Text Notation

Some examples show modifications to text in a buffer, with ``before'' and ``after'' versions of the text. These examples show the contents of the buffer in question between two lines of dashes containing the buffer name. In addition, -!- indicates the location of point. (The symbol for point, of course, is not part of the text in the buffer; it indicates the place between two characters where point is located.)

---------- Buffer: foo ----------
This is the -!-contents of foo.
---------- Buffer: foo ----------

(insert "changed ")
     => nil
---------- Buffer: foo ----------
This is the changed -!-contents of foo.
---------- Buffer: foo ----------