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On 15-Oct-05, at 5:51 PM, David Given wrote:

...actually, a thought: if I were to run Lua in an environment managed by a *real* garbage collector, lik the Boehm libgc, would it be worth my while to
disable Lua's own garbage collector? If so, how?

That's an interesting question.

First of all, if I had written Lua's garbage collector, I would have taken offence to your use of *real*. The Lua GC is a real garbage collector, and quite a reasonable one. It suffers from not being integrated with a memory
allocator, perhaps, but the consequence is that it is fully portable.

Nonetheless, one might wish to integrate Lua's memory management with the memory management available in some external environment. This will prove to be tricky, because the Lua data structures used to support its garbage collection are also used for other purposes. So it would be necessary to
disentangle some of the linked lists.

Beyond that, the Lua garbage collector performs some tasks which are quite specific to Lua's semantics. For example, the Boehm garbage collector does not really have any mechanism equivalent to Lua's weak tables, or even any mechanism which could easily be used to implement weak tables. And, while the Boehm collector can implement finalization, it does not do so in a way consistent with Lua's (arguably idiosyncratic) semantics, which could, in theory, be used to change, add or delete __gc metamethods during the life
span of an object, something not normally contemplated by finalization

That's not to say that it couldn't be done, of course.