Perl 6 regexes, the heart of NQP-rx

• Perl 6 introduced protoregexes in 2008

• Protoregexes are key to Perl 6 language extensibility

• Would result in fourth rewrite of PGE

• July 2009: decided to add regexes to NQP

• September 2009: decided that regex engine should be written in Perl 6 syntax
• → Started NQP-rx

• October 2009: wrote NQP-rx using NQP-rx (self-hosting)