Escaping the Filter command's wildcards

[Paul Dupuis]

The filter command in LiveCode appears to accept a regular expression
(using ? for a single character match, * for multiple character match,
[chars] and [char-char]). However, if you want to filter a container to
a string where you pattern contains a question mark, it does not appear
that you can escape the ? with \? in the pattern to have it treated as a
"real" question mark instead of a wild card.

While \? does not cause ? to be treated as a question mark instead of a
wild card, using [?] does appear to treat it as a real character and not
as a wild card.

Does any one have any knowledge of escaping the special characters
listed in the Dictionary? Or whether other regex special characters can
be used beyond those listed?