use strict;
use warnings;

my $a='
$text=~s#Find \#Text#Replace Text#;
$text=~s/Find \/Text/Replace Text/;
$text=~s{Find \}Text}{Replace Text};
';

if ($a =~ 
/		# start
\$text=~s	# remember to escape the $ to avoid interpolation
(.)		# capture the '#'
(.*?)		# match any non-newline character non-greedily
(?<!\\)		# make sure the '#' is not escaped in your data
\1		# the first unescaped '#'
(.*?)		# match any non-newline character non-greedily
\1;		# the second '#'
/x		# end
)


{
    # need value $findtext='Find \#Text';
    print "$2\n";
    # need value $repltext='Replace Text';    
    print "$3\n"
}