PCRE2 is the name used for a revised API for the PCRE library, which is a set of functions, written in C, that implement regular expression pattern matching using the same syntax and semantics as Perl, with just a few differences. Some features that appeared in Python and the original PCRE before they appeared in Perl are also available using the Python syntax.
This provides some C++ wrapper functions to provide some useful utilities like regex match and regex replace.