$ perl -wE'
for my $num (0..3) {
$num or do { say "$num is false"; next };
say "num $num"
}'
0 is false
num 1
num 2
num 3

#! /usr/bin/perl
use strict;
use warnings;


my @files = (
    $0,                      # dieses Skript
    'nicht.da.txt',          # nicht existent
    $0,                      # dieses Skript
);


for my $file ( @files ) {

    open my $infh, '<', $file or do { warn "open($file,ro) failed: $!\n"; next; };

    # ...

    print "file is open: $file: ", ref( $infh ), $/;
}

file is open: a3.pl: GLOB
open(nicht.da.txt,ro) failed: No such file or directory
file is open: a3.pl: GLOB