There are some predefined character classes. The \s matches a whitespace character [\t\n\t\f\v], the \d a digit [0-9], and the \w a word character [a-zA-Z0-9_]. named_character_class.py #!/usr/bin/python import re text = 'We met in 2013. She must be now about 27 ...
Character classes such as \w or \S (defined below) are also accepted inside a set, although the characters they match depends on whether ASCII or LOCALE mode is in force. Characters that are not within a range can be matched by complementing the set. If the first character of the set ...
正则表达式(Regular Expression)通常被用来检索、替换那些符合某个模式(规则)的文本。 此处的Regular即是规则、规律的意思,Regular Expression即“描述某种规则的表达式”之意。 本文收集了一些常见的正则表达式用法,方便大家查询取用,并在最后附了详细的正则表达式语法手册。 案例包括:「邮箱、身份证号、手机号码、固定电...
Inside the regular expression, a dot operators represents any character except the newline character, which is\n. Any character means letters uppercase or lowercase, digits 0 through 9, and symbols such as the dollar ($) sign or the pound (#) symbol, punctuation mark (!) such as the que...
Write a Python program to find all five-character words in a string. Click me to see the solution 34. Find 3-5 Letter Words Write a Python program to find all three, four, and five character words in a string. Click me to see the solution ...
Metacharacters are not active inside classes. For example,[akm$]will match any of the characters'a','k','m', or'$';'$'is usually a metacharacter, but inside a character class it’s stripped of its special nature. You can match the characters not listed within the class bycomplementing...
Most of the standard escapes supported by Python string literals are also accepted by the regular expression parser: \a \b \f \n \r \t \v \x \\ (Note that\bis used to represent word boundaries, and means “backspace” only inside character classes.) ...
\sReturns a match where the string contains a white space character"\s"Try it » \SReturns a match where the string DOES NOT contain a white space character"\S"Try it » \wReturns a match where the string contains any word characters (characters from a to Z, digits from 0-9, an...
在这种情况下,只有用regular expression才能兼顾两种分隔符。可以使用通配符\s*。\s匹配空格或制表符(如只匹配制表符,可使用\t),星号(*)表示这些character可能有多个(其他最常用的通配符见下表),也就是说,相邻的elements是用多个空格或制表符隔开的。 【PS: ①什么是元字符:正则表达式语言的基本字符类型之一。 -...
The third subsection shows how to group subexpressions and how to capture matching text, and the final subsection shows how to use the language’s assertions and flags to affect how regular expressions work. Characters and Character Classes The simplest expressions are just literal characters, such ...