| # | Python regex | What it matches |
|---|---|---|
(?:\(\d+\))?\d+(?:-\d+)*use this |
Phone numbers like (0123)123456, (0123)123-456-789, 123-456, and 123456. |
|
[\w.-]+@[\w.-]+\.[a-zA-Z]{2,3}use this |
Email addresses | |
\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}use this |
IPv4 addresses | |
\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2}use this |
Timestamps like 2006-08-14 02:34:56. |
|
(\$\d{1,3}(?:,\d{3})*(?:\.\d+)?)use this |
Comma-separated currency like $234, $1,234, and $1,234.56. |
|
\d{2,10}use this |
Numbers having 2 to 10 digits. |
Find matching text using Python regex online
awk isn't handy if you want to extract different columns on different rows.
sed is line-oriented, but you want to extract text no matter whether they are in a line or not.
Regex syntax of awk/grep/sed varies slightly, which is a painful to make it right sometimes.
My use cases (see details in this blog post):
- Find all words beginning with a specific prefix.
- Extract fields out from structure text, like Protobuf Message definitions.
- Find specific attributes like hrefs of links in HTML/XML.
Additional resources:
- Python Regex Cheat Sheet | ShortcutFoo
- Pythex: a Python regular expression editor, useful to test regex patterns