__gc visible to lua code...

[Graham Wakefield <lists@...>]

Hi,

Today I discovered that a __gc method installed on a userdata  
metatable is visible to Lua code; when called out of context it is  
likely to cause crashes, so any __gc metamethod in C must typecheck  
the argument.

I was surprised to find this out, I thought __gc would be 'hidden'  
from Lua.  I'm not sure I can think of a reason why you'd want to  
call a userdata's __gc from lua code.

Thought others should know.

Graham