use 5.026;
use Regexp::Common qw[ delimited ];

say '\/';
say $RE{delimited}{ -delim => '\/' };
say '\\/';
say $RE{delimited}{ -delim => '\\/' };
say '\\\/';
say $RE{delimited}{ -delim => '\\\/' };
say '\\\\/';
say $RE{delimited}{ -delim => '\\\\/' };