A quick reference for regular expression syntax.
\d
\D
\w
\W
\s
\S
.
[abc]
[^abc]
[a-z]
^
$
\b
\B
*
+
?
{n}
{n,}
{n,m}
*?
+?
(abc)
(?:abc)
(?<n>abc)
\1
|
(?=abc)
(?!abc)
(?<=abc)
(?<!abc)
g
i
m
s
u
y