Supported Metacharacters

PCRE supports the metacharacters and metasequences listed in Table 43 through Table 47. For expanded definitions of each metacharacter, see "Regex Metacharacters, Modes, and Constructs.”

Table 1-43. PCRE character representations




Alert (bell), \x07.


Backspace, \x08; supported only in character class.


Escape character, \x1B.


Newline, \x0A.


Carriage return, \x0D.


Form feed, \x0C.


Horizontal tab, \x09.


Character specified by a three-digit octal code.


Character specified by a one- or two-digit hexadecimal code.


Character specified by any hexadecimal code.


Named control character.


Character contained by given Unicode block or property.


Character not contained by given Unicode block or property.

Table 1-44. PCRE character classes and class-like constructs




A single character listed, or contained in a listed range.


A single character not listed, and not contained within a listed range.


POSIX-style character class valid only within a regex character class.


Any character, except newline (unless single-line mode, PCRE_DOTALL).


One byte; however, this may corrupt a Unicode character stream.


Word character, [a-zA-z0-9_].


Nonword character, [^a-zA-z0-9_].


Digit character, [0-9].


Nondigit character, [^0-9].


Whitespace character, [\n\r\f\t\v ].


Nonwhitespace character, [^\n\r\f\t\v ].


Unicode newline sequence.

Table 1-45. PCRE anchors and zero-width tests




Start of string, ...

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