The following table describes the escape characters and sequences that can be used in regular expressions:
Table B.1  | List of Character Escapes  | 
 
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(Ordinary characters) 
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Characters other than . $ ^ { [ ( | ) * + ? \ match themselves. 
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\a 
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Matches a bell (alarm) \u0007. 
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\t 
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Matches a tab \u0009. 
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\r 
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Matches a carriage return \u000D. 
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\v 
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Matches a vertical tab \u000B. 
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\f 
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Matches a form feed \u000C. 
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\n 
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Matches a new line \u000A. 
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\e 
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Matches an escape \u001B. 
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\040 
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Matches an ASCII character as octal (exactly three digits). The character \040 represents a space. 
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\x20 
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Matches an ASCII character using hexadecimal representation (exactly two digits). 
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\u0020 
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Matches a Unicode character using hexadecimal representation (exactly four digits). 
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\ 
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When followed by a character that is not recognized as an escaped character, matches that character. For example, \* is the same as \x2A. 
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