Re^5: Is it possible to create a sub exclusive to a sub? (nasty memory leak)

What I meant was that the subroutine, if written as a named subroutine, isn't a closure. By making it lexical and anonymous you make it one though, ...

That makes no sense to me, but I have a fuzzy definition of Perl's closures, so that may not be surprising.

The confusing part is this.

{
    my $foo = 1;
    sub get_and_inc_foo { $foo++ }
}
[download]

I was always told that get_and_inc_foo() is a closure over $foo. But, it's neither anonymous nor lexical, so how does that work?

If my example is a closure, then aren't all subroutines closures over the file-scoped lexicals in the file they're defined in?

(Now that I think of it, isn't this the reason why you cannot have globals when using ModRegistry?)

------
We are the carpenters and bricklayers of the Information Age.

Then there are Damian modules.... *sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon. - flyingmoose

I shouldn't have to say this, but any code, unless otherwise stated, is untested

Comment on Re^5: Is it possible to create a sub exclusive to a sub? (nasty memory leak) Download Code

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Re^6: Is it possible to create a sub exclusive to a sub? (nasty memory leak) by ihb (Deacon) on Sep 19, 2004 at 14:30 UTC
`&get_and_inc_foo` is a closure, because it binds a lexical variable defined outside of it. If my example is a closure, then aren't all subroutines closures over the file-scoped lexicals in the file they're defined in? If they don't use any lexicals defined outside them, they're not closures. `sub foo { 1 }` isn't a closure no matter where it's defined. `my $foo; sub closure { $foo } sub not_closure { 1 }` [download] What I mean with making the subroutine a lexical anonymous subroutine is the following. `my $foo; # lexical $foo = sub { $foo->() }; # closure local $bar; # dynamical $bar = sub { $bar->() }; # not a closure` [download] `ihb` Read argumentation in its context!	[reply] [d/l] [select]
Re^7: Is it possible to create a sub exclusive to a sub? (nasty memory leak) by dragonchild (Archbishop) on Sep 19, 2004 at 18:30 UTC
So, if I had something like: `package main; my $foo = 1; sub foobar { $foo++; }` [download] Does that make foobar() a closure? ------ We are the carpenters and bricklayers of the Information Age. Then there are Damian modules.... sigh* ... that's not about being less-lazy -- that's about being on some really good drugs -- you know, there is no spoon.* - flyingmoose I shouldn't have to say this, but any code, unless otherwise stated, is untested	[reply] [d/l]
Re^8: Is it possible to create a sub exclusive to a sub? (nasty memory leak) by ihb (Deacon) on Sep 19, 2004 at 21:27 UTC
Yes. `ihb` Read argumentation in its context!	[reply] [d/l]


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