regex-rs

Regex automata construction, minimization, visualization, and simulation.

Example: ab(34)+|12(34)*

Dependencies

• Graphviz

Supported Syntax and Notes

The alphabet consists of all unicode scalar values.

All base regex operations (concatenation, union (|), groups ((...)), and Kleene star (*)) are supported.

Additionally supported:

• Wildcard .
• Repetition metacharacters +, ?
• Repetition ranges {min, max}, {n}, {n,}
• Character ranges [...]
• Character classes \w, \d, \s
• Scoped backreferences (\n where 1 <= n <= u64::MAX)
• Hex escapes (\xnn, \unnnn where n is a hexidecimal digit)

Citations

• Aho, A. V., Sethi, R., & Ullman, J. D. (2002). Compilers: Principles, techniques, and Tools Sections 3.6, 3.7. Addison-Wesley.
• Hopcroft, John. "An n log n algorithm for minimizing states in a finite automaton." Theory of machines and computations. Academic Press, 1971. 189-196.
• Yingjie, X. U. "Describing an n log n algorithm for minimizing states in deterministic finite automaton." (2009): 2008-2009.