PCRE2 - Perl-compatible regular expressions (revised API) .rs #include <pcre2.h>

 int pcre2_set_compile_extra_options(pcre2_compile_context *ccontext,  " uint32_t extra_options);" 

. .rs This function sets additional option bits for pcre2_compile() that are housed in a compile context. It completely replaces all the bits. The extra options are: PCRE2_EXTRA_ALLOW_LOOKAROUND_BSK Allow \eK in lookarounds JOIN
PCRE2_EXTRA_ALLOW_SURROGATE_ESCAPES Allow \ex{d800} to \ex{dfff} in UTF-8 and UTF-32 modes JOIN
PCRE2_EXTRA_ALT_BSUX Extended alternate \eu, \eU, and \ex handling PCRE2_EXTRA_ASCII_BSD \ed remains ASCII in UCP mode PCRE2_EXTRA_ASCII_BSS \es remains ASCII in UCP mode PCRE2_EXTRA_ASCII_BSW \ew remains ASCII in UCP mode JOIN
PCRE2_EXTRA_ASCII_DIGIT [:digit:] and [:xdigit:] POSIX classes remain ASCII in UCP mode JOIN
PCRE2_EXTRA_ASCII_POSIX POSIX classes remain ASCII in UCP mode JOIN
PCRE2_EXTRA_BAD_ESCAPE_IS_LITERAL Treat all invalid escapes as a literal following character JOIN
PCRE2_EXTRA_CASELESS_RESTRICT Disable mixed ASCII/non-ASCII case folding PCRE2_EXTRA_ESCAPED_CR_IS_LF Interpret \er as \en PCRE2_EXTRA_MATCH_LINE Pattern matches whole lines PCRE2_EXTRA_MATCH_WORD Pattern matches "words" There is a complete description of the PCRE2 native API in the HREF
pcre2api
page and a description of the POSIX API in the HREF
pcre2posix
page.