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Regex Notation
Regex Quick Reference
Symbol | Description | |
---|---|---|
[abc] | A single character: a, b or c | |
[ | abc] | Any single character but a, b, or c |
[a-z] | Any single character in the range a-z | |
[a-zA-Z] | Any single character in the range a-z or A-Z | |
Start of line | ||
$ | End of line | |
\A | Start of string | |
\z | End of string | |
. | Any single character | |
\s | Any whitespace character | |
\S | Any non-whitespace character | |
\d | Any digit | |
\D | Any non-digit | |
\w | Any word character (letter, number, underscore) | |
\W | Any non-word character | |
\b | Any word boundary character | |
(…) | Capture everything enclosed | |
(a | b) | a or b |
a? | Zero or one of a | |
a* | Zero or more of a | |
a+ | One or more of a | |
a{3} | Exactly 3 of a | |
a{3,} | 3 or more of a | |
a{3,6} | Between 3 and 6 of a |
options:
i case insensitive m make dot match newlines x ignore whitespace in regex o perform #{...} substitutions only once