grex is a library as well as a command-line utility that is meant to simplify the often complicated and tedious task of creating regular expressions. It does so by automatically generating a single regular expression from user-provided test cases. The resulting expression is guaranteed to match the test cases which it was generated from. This project has started as a Rust port of the JavaScript tool regexgen written by Devon Govett. Although a lot of further useful features could be added to it, its development was apparently ceased several years ago. The plan is now to add these new features to grex as Rust really shines when it comes to command-line tools. grex offers all features that regexgen provides, and more. The philosophy of this project is to generate the most specific regular expression possible by default that exactly matches the given input only and nothing else. With the use of command-line flags (in the CLI tool) or preprocessing methods (in the library).
Features
- Detection of common prefixes and suffixes
- Detection of repeated substrings and conversion to {min,max} quantifier notation
- Alternation using | operator
- Fully compliant to newest Unicode Standard 13.0
- Capturing or non-capturing groups
- Reads input strings from the command-line or from a file