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Dec 8, 2017 - 1 minute read - python

Regular Expressions

A regex cheatsheat.

* Matches the preceding character zero or more times
? Matches preceding character ZERO or ONE 
+ Matches preceding character ONE or MORE times
. Matches any ONE character except a newline
| OR
^ Matches the beginning of lines
[^] ^ When used inside square brackets will match any character not in class
$ Matches the end of a line
\A matches only at the start of a string
\Z matches only at the end of the string
\b word boundary
() Used for grouping
{m,n} at least m occurrences of the preceding character and at most n
[0-9]{3,5} Will match at least 3 occurrences of 0-9 and at most 6


\d Matches any decimal digit == [0-9]
\D Matches any non-digit character == [^0-9]
\s Matches any whitespace character == [ \t\n\r\f\v]
\S Matches an non-whitespace character == [^ \t\n\r\f\v]
\w Matches any alphanumeric character == [-zA-Z0-9_]
\W Matches any non-alphanumeric character == [^-zA-Z0-9_]
re.DOTALL will match a newline using .

Python regex tutorial

Python3 re module documentation