Regexes

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A single character of: a, b, or c:

	[abc]

Any single character except: a, b, or c:

	[^abc]
	

Any single character in the range a-z:

	[a-z]
	

Any case insensitive character in the range a-z

	[a-zA-Z]
	

Line starts with:

	^		# Match URLs starting with blog: /^blog/
	

Line ends with:

	$ 		# Match URLs ending with /$blog/
	

Any word boundary:

	\b 		# Effectively implied. Match URLs containing. /\bblog\b/ is the same as /blog/.
	

Start of string:

	\A
	

End of string:

	\z
	

Any single character:

	.
	

Any whitespace character:

	\s
	

Any non-whitespace character:

	\S
	

Any digit:

	\d
	

Any non-digit:

	\D
	

Any word character (letter, number, underscore):

	\w
	

Any non-word character:

	\W
	

Capture everything enclosed:

	(...)
	

a or b:

	(a|b)
	

Zero or one of a:

	a?
	

Zero or more of a:

	a*
	

One or more of a:

	a+
	

Exactly 3 of a:

	a{3}
	

Three or more of a:

	a{3, }
	

Between three and six of a:

	a{3, 6}