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

Sequence

Meaning

\a

Alert (bell), \x07.

\b

Backspace, \x08; supported only in character class.

\e

Escape character, \x1B.

\n

Newline, \x0A.

\r

Carriage return, \x0D.

\f

Form feed, \x0C.

\t

Horizontal tab, \x09.

\octal

Character specified by a three-digit octal code.

\xhex

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

\x{hex}

Character specified by any hexadecimal code.

\cchar

Named control character.

\p{prop}

Character contained by given Unicode block or property.

\P{prop}

Character not contained by given Unicode block or property.

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

Class

Meaning

[...]

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

[^...]

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

[:class:]

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

.

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

\C

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

\w

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

\W

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

\d

Digit character, [0-9].

\D

Nondigit character, [^0-9].

\s

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

\S

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

\R

Unicode newline sequence.

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

Sequence

Meaning

^

Start of string, ...

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