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Beschreibung
Reguläre Ausdrücke sind Muster, mit denen man den Aufbau von Zeichenketten beschreibt.
Characters
| Ausdruck |
Bedeutung
|
x
|
The character x
|
\\
|
The backslash character
|
\0n
|
The character with octal value 0n (0 <= n <= 7)
|
\0nn
|
The character with octal value 0nn (0 <= n <= 7)
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\0mnn
|
The character with octal value 0mnn (0 <= m <= 3, 0 <= n <= 7)
|
\xhh
|
The character with hexadecimal value 0xhh
|
\uhhhh
|
The character with hexadecimal value 0xhhhh
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\t
|
The tab character ('\u0009')
|
\n
|
The newline (line feed) character ('\u000A')
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\r
|
The carriage-return character ('\u000D')
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\f
|
The form-feed character ('\u000C')
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\a
|
The alert (bell) character ('\u0007')
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\e
|
The escape character ('\u001B')
|
\cx
|
The control character corresponding to x
|
Character classes
| Ausdruck |
Bedeutung
|
[abc]
|
a, b, or c (simple class)
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[^abc]
|
Any character except a, b, or c (negation)
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[a-zA-Z]
|
a through z or A through Z, inclusive (range)
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[a-d[m-p]]
|
a through d, or m through p: [a-dm-p] (union)
|
[a-z&&[def]]
|
d, e, or f (intersect1)
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[a-z&&[^bc]]
|
a through z, except for b and c: [ad-z] (subtraction)
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[a-z&&[^m-p]]
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a through z, and not m through p: [a-lq-z](subtraction)
|
Predefined character classes
| Ausdruck |
Bedeutung
|
.
|
Any character
|
\d
|
A digit: [0-9]
|
\D
|
A non-digit: [^0-9]
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\s
|
A whitespace character: [ \t\n\x0B\f\r]
|
\S
|
A non-whitespace character: [^\s]
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\w
|
A word character: [a-zA-Z_0-9]
|
\W
|
A non-word character: [^\w]
|
POSIX character classes (US-ASCII only)
| Ausdruck |
Bedeutung
|
\p{Lower}
|
A lower-case alphabetic character: [a-z]
|
\p{Upper}
|
An upper-case alphabetic character:[A-Z]
|
\p{ASCII}
|
All ASCII:[\x00-\x7F]
|
\p{Alpha}
|
An alphabetic character:[\p{Lower}\p{Upper}]
|
\p{Digit}
|
A decimal digit: [0-9]
|
\p{Alnum}
|
An alphanumeric character:[\p{Alpha}\p{Digit}]
|
\p{Punct}
|
}~
|
\p{Graph}
|
A visible character: [\p{Alnum}\p{Punct}]
|
\p{Print}
|
A printable character: [\p{Graph}]
|
\p{Blank}
|
A space or a tab: [ \t]
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\p{Cntrl}
|
A control character: [\x00-\x1F\x7F]
|
\p{XDigit}
|
A hexadecimal digit: [0-9a-fA-F]
|
\p{Space}
|
A whitespace character: [ \t\n\x0B\f\r]
|
Classes for Unicode blocks and categories
| Ausdruck |
Bedeutung
|
\p{InGreek}
|
A character in the Greek block (simple block)
|
\p{Lu}
|
An uppercase letter (simple category)
|
\p{Sc}
|
A currency symbol
|
\P{InGreek}
|
Any character except one in the Greek block (negation)
|
[\p{L}&&[^\p{Lu}]]
|
Any letter except an uppercase letter (subtraction)
|
Boundary matchers
| Ausdruck |
Bedeutung
|
^
|
The beginning of a line
|
$
|
The end of a line
|
\b
|
A word boundary
|
\B
|
A non-word boundary
|
\A
|
The beginning of the input
|
\G
|
The end of the previous match
|
\Z
|
The end of the input but for the final terminator, if any
|
\z
|
The end of the input
|
Greedy quantifiers
| Ausdruck |
Bedeutung
|
X?
|
X, once or not at all
|
X*
|
X, zero or more times
|
X+
|
X, one or more times
|
X{n}
|
X, exactly n times
|
X(n,}
|
X, at least n times
|
X{n,m}
|
X, at least n but not more than m times
|
Reluctant quantifiers
| Ausdruck |
Bedeutung
|
X??
|
X, once or not at all
|
X*?
|
X, zero or more times
|
X+?
|
X, one or more times
|
X{n}?
|
X, exactly n times
|
X(n,}?
|
X, at least n times
|
X{n,m}?
|
X, at least n but not more than m times
|
Possessive quantifiers
| Ausdruck |
Bedeutung
|
X?+
|
X, once or not at all
|
X*+
|
X, zero or more times
|
X++
|
X, one or more times
|
X{n}+
|
X, exactly n times
|
X(n,}+
|
X, at least n times
|
X{n,m}+
|
X, at least n but not more than m times
|
Logical operators
| Ausdruck |
Bedeutung
|
XY
|
X followed by Y
|
| Y
|
Either X or Y
|
(X)
|
X, as a capturing group
|
Back references
| Ausdruck |
Bedeutung
|
$n
|
Whatever the n-th capturing group matched
|
Quotation
| Ausdruck |
Bedeutung
|
\
|
Nothing, but quotes the following character
|
\Q
|
Nothing, but quotes all characters until \E
|
\E
|
Nothing, but ends quoting started by \Q
|
Special constructs (non-capturing)
| Ausdruck |
Bedeutung
|
(?:X)
|
X, as a non-capturing group
|
(?idmsux-idmsux)
|
Nothing, but turns match flags on - off
|
(?idmsux-idmsux:X)
|
X, as a non-capturing group with the given flags on - off
|
(?=X)
|
X, via zero-width positive lookahead
|
(?!X)
|
X, via zero-width negative lookahead
|
(?<=X)
|
X, via zero-width negative lookahead
|
(?>X)
|
X, as an independent, non-capturing group
|
Embedded flag expressions
| Ausdruck |
Bedeutung
|
(?u)
|
Pattern.UNICODE_CASE
|
(?s)
|
Pattern.DOTALL
|
(?m)
|
Pattern.MULTILINE
|
(?i)
|
Pattern.CASE_INSENSITIVE
|
(?x)
|
Pattern.COMMENTS
|
(?d)
|
Pattern.UNIX_LINES
|
---
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Pattern.CANON_EQ (not available)
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