Nope. Each coderef (set of coderefs in your example - it's the time that the lexical is in scope that matters) has it's own copy. 

sub make_closures
{
  my $value = shift;
  return sub { $value++ }, sub { print "$value\n" }, sub { $value-- };
}

my ($increment, $display, $decrement) = make_closures( 3 );
print "first\n";
$display->();
$increment->();
$display->();
$decrement->();
$display->();

my ($increment2, $display2, $decrement2) = make_closures( 9 );

print "second\n";
$display2->();
$increment2->();
$display2->();
$decrement2->();
$display2->();

print "first again\n";
$display->();
$increment->();
$display->();
$decrement->();
$display->();

[download]

Result: 

first
3
4
3
second
9
10
9
first again
3
4
3

That's why it needs to be lexical.



--Bob Niederman, http://bob-n.com

In reply to Re: Re: Re: Help with the concept of closures. by bobn
in thread Help with the concept of closures. by DigitalKitty

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