foreach (1,2,3,4) {
print "dir1\n" if glob("dir1/f*");
print "dir2\n" if glob("dir2/f*");
}

##</code><code>##


use strict;
use warnings;
use 5.012;

for my $i (1..10) {
    print "$i: ";

    if (my $x = glob "dir1/f*") {
        print "\t$x";
    }
    if (my $y = glob "dir2/f*") {
        print "\t$y";
    }

    print "\n";
}

--output:--
1: 	dir1/f1
2: 	dir1/f2
3: 
4: 	dir1/f1
5: 	dir1/f2
6: 
7: 	dir1/f1
8: 	dir1/f2
9: 
10: 	dir1/f1

##</code><code>##

use strict;
use warnings;
use 5.012;

if (my $x = glob "dir1/f*") {
    say $x;
}

if (my $x = glob "dir1/f*") {
    say $x;
}

if (my $x = glob "dir1/f*") {
    say $x;
}

if (my $x = glob "dir1/f*") {
    say $x;
}
if (my $x = glob"dir1/f*") {
    say $x;
}

--output:--
dir1/f1
dir1/f1
dir1/f1
dir1/f1
dir1/f1