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Date: Wed, 27 Sep 2017 12:39:46 -0700
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Subject: Re: [PHP-DEV] Is reference counting necessary for a PHP
 implementation?
From: smalyshev@gmail.com (Stanislav Malyshev)

Hi!

> Is this statement correct? If I understand correctly many PHP projects
> depend on the deterministic firing of `__destruct()` function to cleanup
> SQL transactions or connections and so forth.

Yes. But, strictly speaking, you do not have to use specifically
refcounting - i.e. having some value to increment by 1 each time
reference is added and decremented by 1 each time reference is removed -
to achieve that. Pretty much none of the code requires there would be an
actual counter - only that the system would behave as if there was a
counter. Of course, in this case actually having the counter is the most
natural way of doing it :) But if you find some other way of achieving
the same semantics, I think it'd be still OK.

> instead could unlock measurable performance improvements, and the behavior
> of destructors could be closely imitated by a combination of try/finally
> and other new language constructs.

I am not sure I am convinced by this statement, and not sure how RAII
patterns would work in GC-based environments (i.e. it seems to me they
won't). That being said, many resource allocation scenarios can be
implemented without RAII (in fact, C doesn't have RAII at all, people
still manage to work with it :).

-- 
Stas Malyshev
smalyshev@gmail.com