Re2c is a free and open-source lexer generator for C, C++ and Go with a
focus on generating fast code. It compiles regular expression
specifications to deterministic finite automata and encodes them in the
form of conditional jumps in the target language. This approach is
generally faster than table-based lexers, and the generated code is easier
to debug and understand. A flexible user interface allows one to adapt the
generated lexer to a particular environment and input model, avoiding the
overhead on unnecessary checks and buffers. Re2c is based on the lookahead
TDFA algorithm that allows it to perform fast and lightweight submatch
extraction.

WWW: https://re2c.org/