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> Regarding those proxies though: I looked in google for lua and proxies,
> and having found nothing, assumed they were not a lua feature.
> Is there any (unofficial/incomplete/whatever) info on them?

Not that I know of. There was a little note from lhf on this list which led
me to look at the source for baselib, and I found them there. Since they
are undocumented, I presume that they are experimental, subject to change,
etc.

But the basic idea is simple enough: Sometimes all you need is a metatable;
creating a whole empty table to attach the metatable to is a bit wasteful.
Creating a zero-length userdata is cheaper, and you can attach a metatable
to it, but the standard interface doesn't allow Lua programs to either
create userdata or manipulate userdata metatables.

Solution: write a little C function which creates a zero-length full
userdata with a specific metatable. The function is, I believe, called
newproxy.

R.

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