It's not a bug in the regex library unless it's a bug in the regex library.
It's not a bug in the regex library unless it's a bug in the regex library.

mockingbirdnest/Principia,pleroy/Principia,mockingbirdnest/Principia,eggrobin/Principia,pleroy/Principia,eggrobin/Principia,eggrobin/Principia,mockingbirdnest/Principia,mockingbirdnest/Principia,pleroy/Principia,pleroy/Principia