Newbie School: Common Regular Expression Operators

Common Regular Expression operators:

Operator	Purpose
.Full stop)	Match any single character.
^Remove font size)	Match an empty string that appears at the beginning of the row or the start of the string.
$Dollar sign)	Match the null string at the end of the row.
A	Match uppercase lettersA.
a	Match lowercase lettersA.
\d	Match any digit.
\D	Match any single non-numeric character.
\w	Matches any single letter or number character. Its synonym is[:alnum:].
[A-E]	Match any uppercaseA, B, C, DOrE.
[^A-E]	MatchDivision A, B, C, DAndEAny character other.
X?	Matches zero or one uppercase letterX.
X*	Match zero or any uppercase lettersX.
X+	Match one or more lettersX.
X{n}	Exact matchNLetter (s)X.
X{n,m}	Least matchedNAnd cannot exceedMLetter (s)X. If omittedM, The expression will try to match at leastN X.
(abc|def)+	Matching a series of at least one)abcOrdef;abcAnddefWill match.

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• Regular Expression

• Understanding Regular Expressions

• Introduction to regular expression syntax in UNIX and Linux Shell