List of characters that have a special meaning for SGML mode.
This list is used when first loading the `sgml-mode' library.
The supported characters and potential disadvantages are:
?\" Makes " in text start a string.
?' Makes ' in text start a string.
?- Makes -- in text start a comment.
When only one of ?\" or ?' are included, "'" or '"', as can be found in
DTDs, start a string. To partially avoid this problem this also makes these
self insert as named entities depending on `sgml-quick-keys'.
Including ?- has the problem of affecting dashes that have nothing to do with comments, so we normally turn it off.