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From: Sebastian Spaeth <Sebastian@sspaeth.de>
To: Austin Clements <amdragon@MIT.EDU>
Subject: Re: Memory management practices
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Date: Mon, 12 Sep 2011 14:30:17 +0200
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Cc: Bertram Felgenhauer <bertram.felgenhauer@googlemail.com>,
	Bart Massey <bart@cs.pdx.edu>, notmuch <notmuch@notmuchmail.org>
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On Fri, 9 Sep 2011 13:53:28 -0400, Austin Clements <amdragon@MIT.EDU> wrote:
> Ah, the *Python* objects don't care, but the underlying C objects do.
[...]

Thanks for the elaboration. I understand now and agree with the analysis..

> Hence my suggestion that, rather than trying to emulate C-style memory
> management in bindings, bindings should create an additional talloc
> reference to the underlying objects and rather than calling
> notmuch_*_destroy during finalization, they should simply unlink this
> additional reference.

Agreed, that sounds like a much better option, although it would keep a
(underlying C object) for Query and all derived Messages around, even
when I explicitely "del query" in python, as long as the python GC keeps
any of those Message() objects alive and around, wouldn't it? (which
would probably be an ok behavior).

But the talloc ref/unref is not exposed through the lib currently, of course.

> Then there's also no need to replicate the library's reference
> structure in the bindings (though there is a danger of needlessly
> delaying free's when the library creates convenience references like
> the one from notmuch_query_t to notmuch_messages_t; for these I'd
> recommend that the bindings undo such references, which requires a
> little knowledge of the library's reference structure, but nothing
> beyond what should be documented).

Right, that would of course solve the above 'problem'.

Sebastian

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