Language extensions for transactions

[Sim <Sim@...>]

I propose to discuss the possibility to extend language and bytecode for transactions and true multithreading.
To do this we need four things:

• + opcodes for begin transaction/commit transaction/rollback transaction
• + C-function similar to lua_xmove, that disconnect GC-aware objects from one lua_State and connect them to another one

Like following example:

transaction --[[
 here VM store stack and code position in current exectuton context
 AND call some impelmentation specific C-function declared like lua_lock
--]]
local someVar = 1
for i=1,10 do
    someVar = someVar + someJob()
    if someVar > 9000 then
        rollback -- here VM reverted to saved position AND call some another C-function
    end
end
commit --[[ here VM call third C-function and ether discard stored position
or work exactly as 'rollback'
--]]

Theese primitives allow to implement modern lock-free multithreading easily so each "real" thread own his 'personal' lua_State and cheaply send and recieve objects to others.

Best regards, Sim.