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== Padrões ==
 
== Padrões ==
−
Classes de caracteres e padrões
+
* Caracteres com funćão especial (devem ser "escaped")
 +
;\ (backslash) :usado para "escape"
 +
;]            :Finaliza uma classe
 +
;^ (caret)    :Nega uma classe
 +
;- (dash)      :Denotes um range
 +
;[a|b|1|2]    :encontra somente a ou b ou 1 ou 2
  
−
;[abc]: a, b ou c
+
* Classes de caracteres e padrões
−
;[a-c]: a, b ou c
 
−
;[0123456789]: qualquer dígito
 
−
;[0-9]:        qualquer dígito
 
−
;[^abc]:      qualquer caractere exceto a ,b ou c
 
  
 +
;[abc] :a, b ou c
 +
;[a-c] :a, b ou c
 +
;[0123456789] :qualquer dígito
 +
;[0-9]  :qualquer dígito
 +
;[^abc] :qualquer caractere exceto a ,b ou c
 +
;\a    :caractere BELL (BEL, 0x07)
 +
;\f    :caractere form feed (FF, 0x0C)
 +
;\n    :caractere fim de linha (LF, 0x0A)
 +
;\r    :caractere carriage return (CR, 0x0D)
 +
;\t    :caractere TAB (HT, 0x09)
 +
;\v    :caractere TAB vertical (VT, 0x0B)
 +
;\xhhhh :caractere Unicode hhhh
 +
;. (dot):qualquer caractere (inclui newline)
 +
;\d    :qualquer dígito [0-9]
 +
;\D    :qualquer não-dígito [^0-9] ou [^\d]
 +
;\s    :espaco em branco. Igual a [ \t\n\r]
 +
;\S    :exceto espaco em branco. Igual a [^ \t\r\n] e  [^\s]
 +
;\w    :word caractere: dígito ou letra. Igual a [a-zA-Z0-9]
 +
;\W    :exceto word caractere
  
−
\a
 
  
−
    This matches the ASCII bell character (BEL, 0x07).
 
−
\f
 
  
−
    This matches the ASCII form feed character (FF, 0x0C).
 
−
\n
 
  
−
    This matches the ASCII line feed character (LF, 0x0A, Unix newline).
+
===Padrões de substituicão (entre parenteses)===
−
\r
 
  
−
    This matches the ASCII carriage return character (CR, 0x0D).
+
;(int|float|double)\s+\w+ :Somente um dos int, float ou double seguida por espaco e algumas letras.
−
\t
+
;(\w+),\1                :Encontra duas palavras repetidas separada por vírgula. Note que \1 repere o padrão
  
−
    This matches the ASCII horizontal tab character (HT, 0x09).
+
* Olhando a frente, inicia com ?= ou ?!
−
\v
 
  
−
    This matches the ASCII vertical tab character (VT, 0x0B).
+
;Bill(?! Gates) :Bill Clinton, Billy the kid, mas não Bill Gates
−
\xhhhh
 
  
−
    This matches the Unicode character corresponding to the hexadecimal number hhhh (between 0x0000 and 0xFFFF). \0ooo (i.e., \zero ooo) matches the ASCII/Latin-1 character corresponding to the octal number ooo (between 0 and 0377).
+
Caracteres especiais em padrões de substituićão
−
. (dot)
+
;\ (backslash) :Escape
 +
;^ (caret) :Comeco de string
 +
;$    :fim de string
 +
;() :denota padrões de substituićào
 +
;{} :quantificadores numéricos
 +
;[] :delimita classes
 +
;|  :ou lógico
 +
;+  :quantificador 1 ou mais
 +
; *  :quantificador 0 ou mais
 +
;?  :quantificador 0 ou 1
  
−
     This matches any character (including newline).
+
== Quantificadores ==
−
\d
+
;{1}    :exatamente 1 ocorrência
 +
;{0,1}  :0 ou 1 ocorrência
 +
;{,1}  :0 ou 1 ocorrência
 +
;{5,10} :5 a 10 ocorrências
 +
;{5,}  :no mínimo 5 ocorrências
 +
; *     :0 ou mais. {0,}
 +
;+      :1 ou mais. {1,}
 +
;?      :0 ou 1 ocorrência. {0,1}
  
−
    This matches a digit. Equal to [0-9]
+
;^\d{4,5}  :qualquer dígito 4 ou 5 vezes. “1234” e “12345”, mas não “567” nem “223459”
−
\D
+
;\s+      :um ou mais espacoes em branco
 +
;(bla){1,} :um ou mais blablabla
 +
;/?>      :encontra “/>” em “<closeditem/>” e “>” em “<openitem>”.
  
−
    This matches a non-digit. Equal to [^0-9] or [^\d]
+
==Assertions==
−
\s
+
;^     : Encontra o início da palavra
 +
;$      : Encontra o fim da palavra
 +
;\b    : Separador de palavras
 +
;\B    : Exceto separador de palavras
  
−
    This matches a whitespace character. Practically equal to [ \t\n\r]
+
===Exemplos===
−
\S
+
;^Peter : Encontra "Peter, hey!" mas não "Hey, Peter!"
 +
;you$  : Encontra "you" em "Me and you" mas não "Are you ok?"
 +
;\bem\b : Encontra "Está em casa" mas não "temos"
 +
;\Bem\B : Encontra "temos" mas não "Está em casa"
  
−
    This matches a non-whitespace. Practically equal to [^ \t\r\n], and equal to [^\s]
 
−
\w
 
  
−
    Matches any “word character” - in this case any letter or digit. Note that underscore (_) is not matched, as is the case with perl regular expressions. Equal to [a-zA-Z0-9]
+
;(?=PATTERN)   : A lookahead assertion looks at the part of the string following a possible match. The positive lookahead will prevent the string from matching if the text following the possible match does not match the PATTERN of the assertion, but the text matched by that will not be included in the result.
−
\W
+
;(?=\w)       : The expression handy(?=\w) will match at “handy” in “handyman” but not in “That came in handy!”
−
 
+
;(?!PATTERN)   : The negative lookahead prevents a possible match to be acknowledged if the following part of the searched string does match its PATTERN.
−
    Matches any non-word character - anything but letters or numbers. Equal to [^a-zA-Z0-9] or [^\w]
+
;\w+\b(?!\s*&) : The expression const \w+\b(?!\s*&) will match at “const char” in the string “const char* foo” while it can not match “const QString” in “const QString& bar” because the “&” matches the negative lookahead assertion pattern.
−
 
 
−
The abbreviated classes can be put inside a custom class, for example to match a word character, a blank or a dot, you could write [\w \.]
 
−
Note
 
−
 
 
−
The POSIX notation of classes, [:<class name>:] is currently not supported.
 
−
Characters with special meanings inside character classes
 
−
 
 
−
The following characters has a special meaning inside the “[]” character class construct, and must be escaped to be literally included in a class:
 
−
 
 
−
]
 
−
 
 
−
    Ends the character class. Must be escaped unless it is the very first character in the class (may follow an unescaped caret)
 
−
^ (caret)
 
−
 
 
−
    Denotes a negative class, if it is the first character. Must be escaped to match literally if it is the first character in the class.
 
−
- (dash)
 
−
 
 
−
    Denotes a logical range. Must always be escaped within a character class.
 
−
\ (backslash)
 
−
 
 
−
    The escape character. Must always be escaped.
 
−
 
 
−
Alternatives: matching “one of”
 
−
 
 
−
If you want to match one of a set of alternative patterns, you can separate those with | (vertical bar character).
 
−
 
 
−
For example to find either “John” or “Harry” you would use an expression John|Harry.
 
−
Sub Patterns
 
−
 
 
−
Sub patterns are patterns enclosed in parentheses, and they have several uses in the world of regular expressions.
 
−
Specifying alternatives
 
−
 
 
−
You may use a sub pattern to group a set of alternatives within a larger pattern. The alternatives are separated by the character “|” (vertical bar).
 
−
 
 
−
For example to match either of the words “int”, “float” or “double”, you could use the pattern int|float|double. If you only want to find one if it is followed by some whitespace and then some letters, put the alternatives inside a subpattern: (int|float|double)\s+\w+.
 
−
Capturing matching text (back references)
 
−
 
 
−
If you want to use a back reference, use a sub pattern to have the desired part of the pattern remembered.
 
−
 
 
−
For example, if you want to find two occurrences of the same word separated by a comma and possibly some whitespace, you could write (\w+),\s*\1. The sub pattern \w+ would find a chunk of word characters, and the entire expression would match if those were followed by a comma, 0 or more whitespace and then an equal chunk of word characters. (The string \1 references the first sub pattern enclosed in parentheses)
 
−
Lookahead Assertions
 
−
 
 
−
A lookahead assertion is a sub pattern, starting with either ?= or ?!.
 
−
 
 
−
For example to match the literal string “Bill” but only if not followed by “ Gates”, you could use this expression: Bill(?! Gates). (This would find “Bill Clinton” as well as “Billy the kid”, but silently ignore the other matches.)
 
−
 
 
−
Sub patterns used for assertions are not captured.
 
−
 
 
−
See also Assertions
 
−
Characters with a special meaning inside patterns
 
−
 
 
−
The following characters have meaning inside a pattern, and must be escaped if you want to literally match them:
 
−
 
 
−
\ (backslash)
 
−
 
 
−
    The escape character.
 
−
^ (caret)
 
−
 
 
−
    Asserts the beginning of the string.
 
−
$
 
−
 
 
−
    Asserts the end of string.
 
−
() (left and right parentheses)
 
−
 
 
−
    Denotes sub patterns.
 
−
{} (left and right curly braces)
 
−
 
 
−
    Denotes numeric quantifiers.
 
−
[] (left and right square brackets)
 
−
 
 
−
    Denotes character classes.
 
−
| (vertical bar)
 
−
 
 
−
    logical OR. Separates alternatives.
 
−
+ (plus sign)
 
−
 
 
−
    Quantifier, 1 or more.
 
−
* (asterisk)
 
−
 
 
−
    Quantifier, 0 or more.
 
−
? (question mark)
 
−
 
 
−
    An optional character. Can be interpreted as a quantifier, 0 or 1.
 
−
 
 
−
Prev Contents Next
 
−
Regular Expressions Regular Expressions Quantifiers
 
−
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−
Send feedback to the KDE Docs Team
 

Edição atual tal como às 15h02min de 24 de maio de 2015

Breve resumo de expressões regulares para o Kate.

Veja www.kate-editor.org/doc/regular-expressions.html

Padrões

  • Caracteres com funćão especial (devem ser "escaped")
\ (backslash) 
usado para "escape"
]  
Finaliza uma classe
^ (caret)  
Nega uma classe
- (dash)  
Denotes um range
[a|b|1|2]  
encontra somente a ou b ou 1 ou 2
  • Classes de caracteres e padrões
[abc] 
a, b ou c
[a-c] 
a, b ou c
[0123456789] 
qualquer dígito
[0-9]  
qualquer dígito
[^abc] 
qualquer caractere exceto a ,b ou c
\a  
caractere BELL (BEL, 0x07)
\f  
caractere form feed (FF, 0x0C)
\n  
caractere fim de linha (LF, 0x0A)
\r  
caractere carriage return (CR, 0x0D)
\t  
caractere TAB (HT, 0x09)
\v  
caractere TAB vertical (VT, 0x0B)
\xhhhh 
caractere Unicode hhhh
. (dot)
qualquer caractere (inclui newline)
\d  
qualquer dígito [0-9]
\D  
qualquer não-dígito [^0-9] ou [^\d]
\s  
espaco em branco. Igual a [ \t\n\r]
\S  
exceto espaco em branco. Igual a [^ \t\r\n] e [^\s]
\w  
word caractere: dígito ou letra. Igual a [a-zA-Z0-9]
\W  
exceto word caractere



Padrões de substituicão (entre parenteses)

(int|float|double)\s+\w+ 
Somente um dos int, float ou double seguida por espaco e algumas letras.
(\w+),\1  
Encontra duas palavras repetidas separada por vírgula. Note que \1 repere o padrão
  • Olhando a frente, inicia com ?= ou ?!
Bill(?! Gates) 
Bill Clinton, Billy the kid, mas não Bill Gates

Caracteres especiais em padrões de substituićão

\ (backslash) 
Escape
^ (caret)  
Comeco de string
$  
fim de string
() 
denota padrões de substituićào
{} 
quantificadores numéricos
[] 
delimita classes
|  
ou lógico
+  
quantificador 1 ou mais
*  
quantificador 0 ou mais
?  
quantificador 0 ou 1

Quantificadores

{1}  
exatamente 1 ocorrência
{0,1}  
0 ou 1 ocorrência
{,1}  
0 ou 1 ocorrência
{5,10} 
5 a 10 ocorrências
{5,}  
no mínimo 5 ocorrências
*  
0 ou mais. {0,}
+  
1 ou mais. {1,}
?  
0 ou 1 ocorrência. {0,1}
^\d{4,5}  
qualquer dígito 4 ou 5 vezes. “1234” e “12345”, mas não “567” nem “223459”
\s+  
um ou mais espacoes em branco
(bla){1,} 
um ou mais blablabla
/?>  
encontra “/>” em “<closeditem/>” e “>” em “<openitem>”.

Assertions

^  
Encontra o início da palavra
$  
Encontra o fim da palavra
\b  
Separador de palavras
\B  
Exceto separador de palavras

Exemplos

^Peter 
Encontra "Peter, hey!" mas não "Hey, Peter!"
you$  
Encontra "you" em "Me and you" mas não "Are you ok?"
\bem\b 
Encontra "Está em casa" mas não "temos"
\Bem\B 
Encontra "temos" mas não "Está em casa"


(?=PATTERN)  
A lookahead assertion looks at the part of the string following a possible match. The positive lookahead will prevent the string from matching if the text following the possible match does not match the PATTERN of the assertion, but the text matched by that will not be included in the result.
(?=\w)  
The expression handy(?=\w) will match at “handy” in “handyman” but not in “That came in handy!”
(?!PATTERN)  
The negative lookahead prevents a possible match to be acknowledged if the following part of the searched string does match its PATTERN.
\w+\b(?!\s*&) 
The expression const \w+\b(?!\s*&) will match at “const char” in the string “const char* foo” while it can not match “const QString” in “const QString& bar” because the “&” matches the negative lookahead assertion pattern.
Disponível em "http://hunter.mat.ufrgs.br/mediawiki/index.php?title=Regular_expression&oldid=4040"