Regex regex

misc.txt

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Regex Patterns

\d - digit [0,9]
\w - digit, ASCII letter or underscore
\s - whitespace, i.e. space, tab, newline(\n), carriage return(\r), vertical tab(Ctrl + K) <-vertical tab not useful anymore

\D == [^\d] - 1 character which is not digit
\W == [^\w] - 1 character which is not ASCII letter, digit and underscore
\S == [^\s] - 1 character which is not type of whitespace

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^ - 	Start of string, Ex : ^abc accept if string starts with abc
$ -   End of string or end of line, Ex: .*? the end$	-> this is the end
. -   Any character except \n (line break)
\ -   Escape character for reserved words. Ex : 1) \.\*\+\?  \$\^\/\\ -> *+?    $^/\ 2) 	\[\{\(\)\}\]	-> [{()}]   
? -   1 time on none Ex : 	plurals?	plural
* -   0 or more Ex: 	A*B*C*	AAACC
+ -   1 or more

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{3}	  - exactly 3 times, Ex: 	\D{3} -> ABC
{2,4} - 2 to 4 times,    Ex:  \d{2,4}	-> 156
{3,}  - 3 or more times  Ex:  \w{3,}	regex_tutorial

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|	    - OR operand, Ex:	22|33	 -> 33
(…)	    - Capturing group,	Ex: A(nt|pple) ->	Apple (captures "pple")
\1	    - Type of First Group parantheses, Ex: 	r(\w)g\1x	-> regex(Here is \1 is type of \w)
\2	    - Type of Second Group parantheses,	(\d\d)\+(\W\d)=\2\+\1	-> 12+,5=,5+12(Here is \1 is type of \d\d and \2 is type of \W\d)
(?:…)	- Non-capturing group, Ex: 	A(?:nt|pple)	-> Apple(Here is pple or not "nt" is acceptable)

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[ … ]   - 	One of the characters in the brackets, Ex: 1)[AEIOU]	-> 1 uppercase vowel 2) T[ao]p	-> Tap or Top
-	    -   Range indicator, Ex:	[a-z]	-> 1 lowercase letter
Ex: [x-y]	 -   One of the characters in the range from x to y
    [^x]	 -   One character that is not x
    [^x-y]   -   One of the characters not in the range from x to y



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\t   - tab character, Ex: T\t\w{2}	-> T     ab
\r   - carriage return
\n   - Line feed
\r\n - Line separator on Windows
\h   - 1 horizontal whitespace character: tab or Unicode space separator
\N   - [^\n] 1 character is not \n
\H   - [^\h] 1 character is not \h

regex.txt

https://www.regextester.com

rewrite.txt

%1 Refers to a pattern matched in a RewriteCond condition
$1 refers to a pattern matched inside a RewriteRule.