# 0. Just-in-time variable declaration and initialization.

##</code><code>##

# 1. Variables in consistent case (all lower or all upper)

# 2. Each dictionary word in the variable name separated 
#    by underscore, unless accepted as one word by usage as 
#    in 'username' or 'logout'

# 3. Package variables in all caps, used for things like 
#    config values
use vars qw(
	$FOO
	$BAR
	$BAZ
	$FOO_BAR
);

##</code><code>##

# 4. Global lexicals in all lower case, and 
#     prefixed with some text to mark them as such.
#     For example...
my ($glob_foo, $glob_bar, $glob_baz, @glob_foo_bar);

##</code><code>##

# 5. Local lexicals on all lowercase
sub foo {
	my ($bar) = @_;
	for (@$bar) {
		print "yay" if ($_ eq $FOO);
	}
	return $bar;
}

##</code><code>##

# 5.5. Use prefixes to scope other logically different 
#      vars. For example, 'cgi_' to prefix vars holding 
#      params delivered via the cgi
my $cgi_foo = $cgi->param('foo');
my $cgi_bar = $cgi->param('bar');

# 6. Refs prefixed with the appropriate identifier. I wish 
#     Perl would extend the "different things look different" 
#     to enable easy identification of the kind of data 
#     structure a ref refers to.
my $aref_bar = foo(\@foo_bar);

# 7. Rules 1-5 apply to rule 6 as well... so, an array ref 
#    inside a sub would be $this_aref_bar, etc.

##</code><code>##

# 8. modified: I like camelCase, however, the real purpose
# here is to visually distinguish a sub from a var. Choose 
# your method

# 9. Subroutines not exported from a package prefixed with 
#    an underscore
package Foo;
@EXPORT = qw(
  startProgram
  watchOut
  goHome
);

sub startProgram {
	_wakeUp();
}

sub watchOut {
	_keepEyeOpen();
}

sub goHome {
	_nightyNight();
}

sub _wakeUp {}
sub _keepEyeOpen {}
sub _nightyNight {}

# 9.5. Never export anything by default.

@EXPORT_OK

##</code><code>##

# 10. Always pass named vars to subs
doThis('with' => $that, 'and' = $something_else);