# 1A. not very anal, but more concise
for my $dir (glob "*") {
    # for a brief moment, $dir might not hold a directory's name
    next unless -d $dir; 
    ...
}

##</code><code>##

# 1B. more "correct", with additional related variable
for my $dir0 (glob "*") {
    # a "0" suffix is my convention for variables that contain an unprocessed value 
    next unless -d $dir0;
    my $dir = $dir0;
    ...
}

##</code><code>##

# 1C. more "correct", with additional variable and concept
for my $entry (glob "*") {
    next unless -d $entry;
    my $dir = $entry;
    ...
}

##</code><code>##

# 2A. not very anal
sub load {
    # actually, module can be in the form of "Foo::Bar" or "Foo/Bar.pm".
    # but will be canonicalized to "Foo/Bar.pm" form 
    my $module = shift; 
    if ($module =~ /\A\w+(::\w+)*\z/) {
        $module = join("/", split /::/, $module) . ".pm";
    }
    ...
}

##</code><code>##

# 2B.
sub load {
    my $arg = shift; 
    my $module_pm;
    if ($arg =~ /\A\w+(::\w+)*\z/) {
        $module_pm = join("/", split /::/, $arg) . ".pm";
    } else {
        $module_pm = $arg;
    }
    ...
}