use strict;
use warnings;

sub foo {
    next LOOP;
}

LOOP: for ( 1 .. 10 ) {
    if ( $_ < 5 ) {
        foo();
    }
    print "$_\n";
}
----
Exiting subroutine via next at ./test.pl line 7.
Exiting subroutine via next at ./test.pl line 7.
Exiting subroutine via next at ./test.pl line 7.
Exiting subroutine via next at ./test.pl line 7.
5
6
7
8
9
10

##</code><code>##

while ( <FH> ) {
    next unless length; # Skip blank lines
    next if /^#/;       # Skip comments
    next if /\bSKIP\b/; # Skip lines that want to be skipped

    # Do something useful here
}

##</code><code>##

while ( <FH> ) {
    if ( length ) {
        if ( !/^#/ ) {
            if ( !/\bSKIP\b/ ) {
                # Do something useful here
            }
        }
    }
}