#!/usr/bin/perl -w

package Szywiecki;

$Robert = "the boss";

sub terminate {
		my $name = shift;
		print "$Robert has canned $name's sorry butt\n";
}

terminate("arturo"); # prints "the boss has canned arturo's sorry butt"

##</code><code>##

#!/usr/bin/perl -w

use strict;

$Robert = "the boss";
print "\$Robert = $Robert\n";

##</code><code>##

#!/usr/bin/perl -w

use strict;

$main::Robert = "the boss";
print "\$main::Robert = $main::Robert\n";

##</code><code>##

#!/usr/bin/perl -w

package Szyewicki;

$Robert = "the boss";

package PoolHall;

$Robert = "the darts expert";

package Sywiecki; # back to work!

print "Here at work, 'Robert' is $Robert, but over at the pool hall, 'Robert'
is $PoolHall::Robert\n";

##</code><code>##

#!/usr/bin/perl -w

use strict;

#remember we're in package main

use vars qw($foo);

$foo = "Yo!"; # sets $main::foo

print "\$foo: $foo\n"; # prints "Yo!"

my $foo = "Hey!"; # this is a file-level my variable!

print "\$foo: $foo\n"; # prints "Hey!" -- new declaration 'masks' the old one

{ # start a block
		my $foo = "Yacht-Z";
		print "\$foo: $foo\n"; 
		# prints "Yacht-Z" -- we have a new $foo in scope.
		print "\$main::foo: $main::foo\n"; 
		# we can still 'see' $main::foo
		subroutine();
} # end that block

print "\$foo: $foo\n"; # there it is, our file-level $foo is visible again!

print "\$main::foo: $main::foo\n"; # whew!  $main::foo is still there!

sub subroutine {
		print "\$foo: $foo\n"; # prints "Hey!"
		# why?  Because the variable declared in the naked block
		# is no longer in scope -- we have a new set of braces.
		# but the file-level variable is still in scope, and
		# still 'masks' the declaration of $main::foo
}

package Bar;

print "\$foo: $foo\n"; # prints "Hey!" -- the my variable's still in scope
# if we hadn't made that declaration above, this would be an error: the
# interpreter would tell us that Bar::foo has not been defined.

##</code><code>##

#!/usr/bin/perl -w

use strict;

use vars qw ($foo); # or "our $foo" if you're using 5.6

$foo = "global value";

print "\$foo: $foo\n"; # prints "global value"

sub mysub {
	my $foo = "my value";
	showfoo(); # prints "global value"
}

sub localsub {
	local $foo = "local value";
	showfoo(); # prints "local value
}

sub showfoo {
	print "\$foo: $foo\n";
}