beginning of the string or after a newline character.
For historical compatibility reasons, @samp{^} can be used only at the
-beginning of the regular expression, or after @samp{\(} or @samp{\|}.
+beginning of the regular expression, or after @samp{\(}, @samp{\(?:}
+or @samp{\|}.
@item @samp{$}
@cindex @samp{$} in regexp
@table @samp
@item [:ascii:]
-This matches any @acronym{ASCII} (unibyte) character.
+This matches any @acronym{ASCII} character (codes 0--127).
@item [:alnum:]
This matches any letter or digit. (At present, for multibyte
characters, it matches anything that has word syntax.)
@item [:lower:]
This matches any lower-case letter, as determined by
the current case table (@pxref{Case Tables}).
+@item [:multibyte:]
+This matches any multibyte character (@pxref{Text Representations}).
@item [:nonascii:]
-This matches any non-@acronym{ASCII} (multibyte) character.
+This matches any non-@acronym{ASCII} character.
@item [:print:]
This matches printing characters---everything except @acronym{ASCII} control
characters and the delete character.
@item [:space:]
This matches any character that has whitespace syntax
(@pxref{Syntax Class Table}).
+@item [:unibyte:]
+This matches any unibyte character (@pxref{Text Representations}).
@item [:upper:]
This matches any upper-case letter, as determined by
the current case table (@pxref{Case Tables}).