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Do you know where your variables are?
 
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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->();

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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