Win8 Strawberry 5.8.9.5 (32)  Tue 06/07/2022 22:09:02
C:\@Work\Perl\monks
>perl

use strict;
use warnings;

my $h1 = 'A3f4';
my $h2 = 'xA3f4';

print hex 'A3f4',  "\n";
print hex $h1,     "\n";
print hex 'xA3f4', "\n";
print hex $h2,     "\n";

print hex '\xA3f4',   "\n";
print hex '\x{A3f4}', "\n";

^Z
41972
41972
41972
41972
Illegal hexadecimal digit '\' ignored at - line 13.
0
Illegal hexadecimal digit '\' ignored at - line 14.
0