use warnings;
use 5.010;

for my $num (1 .. 5) {
    my $a = $num;

    {say "in block: $a"};

    sub test {
        say "in function: $a";
    }

    test()
}

--output:--
in block: 1
in function: 1
in block: 2
in function: 1
in block: 3
in function: 1
in block: 4
in function: 1
in block: 5
in function: 1