不理解一段正则表达式语义 [^\"'> \t\)]

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不理解一段正则表达式语义 [^\"'> \t\)]5

[^\"'> \t\)]

1.这段正则表达式是什么意思？
2.\"是对双引号做转义，python正则中还有哪些特殊符号需要\做转义（不考虑\number,\w等），官方文档里写着“permitting you to match characters like "*", "?", and so forth”。我就是想知道so forth里都包括哪些，如果能给出引用地址就更好。

问题补充：根据ihavegotyou提供的“Escape Sequence Meaning Notes”，原正则中的尾部附近的 \) 是不是可以直接写成 )
这样子原正则表达式是不是写成[^\"'> \t)]就好了？

问题补充：比较认同icefishc的说法
虽然在http://www.python.org/doc/2.5/lib/re-syntax.html里有这样的描述：“(Caret.) Matches the start of the string, and in MULTILINE mode also matches immediately after each newline.”
但同时也有这样的描述：“For example, [^5] will match any character except "5"”

感觉python文档关于^的描述有点让我感觉混乱。因为http://www.python.org/doc/2.5/lib/re-syntax.html里，在解释[]时说："^" elsewhere will simply match the "^" character。在解释^时却又说：(Caret.) Matches the start of the string, and in MULTILINE mode also matches immediately after each newline.

Python

2010年1月19日 12:49

photon
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8个答案按时间排序按投票排序

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采纳的答案

The special characters are:

'.'
    (Dot.) In the default mode, this matches any character except a newline. If the DOTALL flag has been specified, this matches any character including a newline.
'^'
    (Caret.) Matches the start of the string, and in MULTILINE mode also matches immediately after each newline.
'$'
    Matches the end of the string or just before the newline at the end of the string, and in MULTILINE mode also matches before a newline. foo matches both ‘foo’ and ‘foobar’, while the regular expression foo$ matches only ‘foo’. More interestingly, searching for foo.$ in 'foo1\nfoo2\n' matches ‘foo2’ normally, but ‘foo1’ in MULTILINE mode; searching for a single $ in 'foo\n' will find two (empty) matches: one just before the newline, and one at the end of the string.
'*'
    Causes the resulting RE to match 0 or more repetitions of the preceding RE, as many repetitions as are possible. ab* will match ‘a’, ‘ab’, or ‘a’ followed by any number of ‘b’s.
'+'
    Causes the resulting RE to match 1 or more repetitions of the preceding RE. ab+ will match ‘a’ followed by any non-zero number of ‘b’s; it will not match just ‘a’.
'?'

Reference:
http://docs.python.org/library/re.html

2010年1月19日 13:13

Ihavegotyou
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在[]中就是表示否定

2010年1月19日 17:17

icefishc
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^符号，本来都具有双义。
建议，对每一个regular expression都操作一下。

2010年1月19日 16:34

Ihavegotyou
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非" 或 ' 或 > 或制表位\t 或 )

2010年1月19日 14:34

icefishc
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后面一个太多了，没有贴完。
()是匹配一个完整的group.
所以，也应该反义.

2010年1月19日 13:24

Ihavegotyou
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     '\A' Matches the start of the string.
    '\b' Matches the empty string that forms the boundary at the beginning or end of a word.
    '\B' Matches the empty string that is not the beginning or end of a word
    '\d' Matches any decimal digit.
    '\D' Matches any non-decimal digit.
   '\s' Matches any whitespace character.
    '\S' Matches any non-whitespace charaacter.
    '\w' Matches any alphanumeric character and the underscore.
    '\W' Matches any non-alphanumeric character.
    '\Z' Matches the end of the string.

Reference:
http://python.about.com/od/regularexpressions/g/regex_spec_char.htm

2010年1月19日 13:09

Ihavegotyou
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Escape Sequence Meaning Notes
------- ------ ------
\newline Ignored
\\ Backslash (\)
\' Single quote (')
\" Double quote (")
\a ASCII Bell (BEL)
\b ASCII Backspace (BS)
\f ASCII Formfeed (FF)
\n ASCII Linefeed (LF)
\N{name} Character named name in the Unicode database (Unicode only)
\r ASCII Carriage Return (CR)
\t ASCII Horizontal Tab (TAB)
\uxxxx Character with 16-bit hex value xxxx (Unicode only) (1)
\Uxxxxxxxx Character with 32-bit hex value xxxxxxxx (Unicode only) (2)
\v ASCII Vertical Tab (VT)
\ooo Character with octal value ooo (3,5)
\xhh Character with hex value hh (4,5)

Reference:
http://www.network-theory.co.uk/docs/pylang/Stringliterals.html