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On 23/06/15 03:57 PM, Sean Conner wrote:

It was thus said that the Great Soni L. once stated:


On 23/06/15 03:19 PM, Rena wrote:

On Tue, Jun 23, 2015 at 2:11 PM, Soni L. <fakedme@gmail.com> wrote:

On 23/06/15 03:09 PM, Sean Conner wrote:

It was thus said that the Great Luiz Henrique de Figueiredo once stated:

co = coroutine.create(function() print"test" end)
...
Can we get a thread metatable?

debug.setmetatable(co,{__len=function(thread) return "abc" end})
print(#co) --> abc

I think the OP wants
         debug.setmetatable(co,{__index=coroutine})
so that he can say co:resume().

    Or

         debug.setmetatable(
                 co,
                 {
                   __call = function(co,...)
                     return coroutine.resume(co,...)
                   end
                 }
         )

so that we can say

         co()

    -spc



And how do you get the status with that?

Not co:status(), that wouldn't work...


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By using both __call and __index.


__call and co() makes it look like a function call, which may be kinda
confusing. On the other hand OOP syntax co:resume() is more Lua-like, as
strings have it too. You also cannot index functions.

   Yes you can.

	function foo(x)
	  return 3 * x + 5
	end

	mt =
	{
	  __index = function(obj,idx)
	    local d = string.dump(obj)
	    return d:sub(idx,idx)
	  end
	}
	
	debug.setmetatable(foo,mt)

Try it without debug.

	
	print(foo[3])
	print(mt.__index[3])

   Granted, this is just a proof-of-concept that simply returns back the
bytecode for a function, but it's easy enough to do other things, say,
return upvalues, local variables, parameters, actual instructions (a byte
index of 3 here returns 'u', part of the Lua signature for a dumped
function:

00000000: 1B 4C 75 61 51 00 01 04 08 04 08 00 07 00 00 00 .LuaQ...........
00000010: 00 00 00 00 40 79 2E 6C 75 61 00 04 00 00 00 06 ....@y.lua......
00000020: 00 00 00 00 01 00 02 04 00 00 00 4E 00 00 80 4C ...........N...L
00000030: 40 C0 00 5E 00 00 01 1E 00 80 00 02 00 00 00 03 @..^............
00000040: 00 00 00 00 00 00 08 40 03 00 00 00 00 00 00 14 .......@........
00000050: 40 00 00 00 00 04 00 00 00 05 00 00 00 05 00 00 @...............
00000060: 00 05 00 00 00 06 00 00 00 01 00 00 00 02 00 00 ................
00000070: 00 00 00 00 00 78 00 00 00 00 00 03 00 00 00 00 .....x..........
00000080: 00 00 00                                        ...

the actual instructions are further in).

   -spc (Will do Stupid Lua Tricks for food 8-)



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