- Results update in real-time as you type.
- Roll over a match or expression for details.
- Save & share expressions with others.
- Use Tools to explore your results.
- Browse the Reference for help & examples.
- Undo & Redo with cmd-Z / Y in editors.
- Search for & rate Community patterns.
RE2 is a fast, safe, thread-friendly alternative to backtracking regular expression engines like those used in PCRE, Perl, and Python. It is a C++ library.
TRE is a lightweight, robust, and efficient POSIX compliant regexp matching library with some exciting features such as approximate (fuzzy) matching.
The matching algorithm used in TRE uses linear worst-case time in the length of the text being searched, and quadratic worst-case time in the length of the used regular expression.