'isprint' option)	*/\p*
\P	like "\p", but excluding digits			*/\P*

NOTE: the above also work for multibyte characters.  The ones below only
match ASCII characters, as indicated by the range.

						*whitespace* *white-space*
\s	whitespace character: <Space> and <Tab>		*/\s*
\S	non-whitespace character; opposite of \s	*/\S*
\d	digit:				[0-9]		*/\d*
\D	non-digit:			[^0-9]		*/\D*
\x	hex digit:			[0-9A-Fa-f]	*/\x*
\X	non-hex digit:			[^0-9A-Fa-f]	*/\X*
\o	octal digit:			[0-7]		*/\o*
\O	non-octal digit:		[^0-7]		*/\O*
\w	word character:			[0-9A-Za-z_]	*/\w*
\W	non-word character:		[^0-9A-Za-z_]	*/\W*
\h	head of word character:		[A-Za-z_]	*/\h*
\H	non-head of word character:	[^A-Za-z_]	*/\H*
\a	alphabetic character:		[A-Za-z]	*/\a*
\A	non-alphabetic character:	[^A-Za-z]	*/\A*
\l	lowercase character:		[a-z]		*/\l*
\L	non-lowercase character:	[^a-z]		*/\L*
\u	uppercase character:		[A-Z]		*/\u*
\U	non-uppercase character:	[^A-Z]		*/\U*

	NOTE: Using the atom is faster than the [] form.

	NOTE: 'ignorecase', "\c" and "\C" are not used by character classes.

			*/\_* *E63* */\_i* */\_I* */\_k* */\_K* */\_f* */\_F*
			*/\_p* */\_P* */\_s* */\_S* */\_d* */\_D* */\_x* */\_X*
			*/\_o* */\_O* */\_w* */\_W* */\_h* */\_H* */\_a* */\_A*
			*/\_l* */\_L* */\_u* */\_U*
\_x	Where "x" is any of the characters above: The character class with
	end-of-line added
(end of character classes)

\e	matches <Esc>					*/\e*
\t	matches <Tab>					*/\t*
\r	matches <CR>					*/\r*
\b	matches <BS>					*/\b*
\n	matches an end-of-line				*/\n*
	When matching in a string instead of buffer text a literal newline
	character is matched.

~	matches the last given substitute string	*/~* */\~*

\(\)	A pattern enclosed by escaped parentheses.	*/\(* */\(\)* */\)*
	E.g., "\(^a\)" matches 'a' at the start of a line.
	There can only be nine of these.  You can use "\%(" to add more, but
	not counting it as a sub-expression.
	*E51* *E54* *E55* *E872* *E873*

\1      Matches the same string that was matched by	*/\1* *E65*
	the first sub-expression in \( and \).
	Example: "\([a-z]\).\1" matches "ata", "ehe", "tot", etc.
\2      Like "\1", but uses second sub-expression,	*/\2*
   ...							*/\3*
\9      Like "\1", but uses ninth sub-expression.	*/\9*
	Note: The numbering of groups is done based on which "\(" comes first
	in the pattern (going left to right), NOT based on what is matched
	first.

\%(\)	A pattern enclosed by escaped parentheses.	*/\%(\)* */\%(* *E53*
	Just like \(\), but without counting it as a sub-expression.  This
	allows using more groups and it's a little bit faster.

x	A single character, with no special meaning, matches itself

							*/\* */\\*
\x	A backslash followed by a single character, with no special meaning,
	is reserved for future expansions

[]	(with 'nomagic': \[])		*/[]* */\[]* */\_[]* */collection* *E76*
\_[]
	A collection.  This is a sequence of characters enclosed in square
	brackets.  It matches any single character in the collection.
	Example		matches ~
	[xyz]		any 'x', 'y' or 'z'
	[a-zA-Z]$	any alphabetic character at the end of a line
	\c[a-z]$	same
	[А-яЁё]		Russian alphabet (with utf-8 and cp1251)

								*/[\n]*
	With "\_" prepended the collection also includes the end-of-line.
	The same can be done by including "\n" in the collection.  The
	end-of-line is also matched when the collection starts with "^"!  Thus
	"\_[^ab]" matches the end-of-line and any character but "a" and "b".
	This makes it Vi compatible: Without the "\_" or "\n" the collection
	does not match an end-of-line.
								*E769*
	When the ']' is not there Vim will not give an error message but
	assume no collection is used.  Useful to search for '['.  However, you
	do get E769 for internal searching.  And be aware that in a
	`:substitute` command the whole command becomes the pattern.  E.g.
	":s/[/x/" searches for "[/x" and replaces it with nothing.  It does
	not search for "[" and replaces it with "x"!

								*E944* *E945*
	If the sequence begins with "^", it matches any