Effil threads compatibility with Lua "classes"

[adrfantini]

Effil threads compatibility with Lua "classes"

[mihacooper]

Hope, problem solved, if not feel free to open another issue

[adrfantini]

If instead of _timersContainerClass I use everywhere, including in the class definition, effil.G._timersContainerClass, everything seems to be working:

Class:

effil = require('effil')

effil.G._timersContainerClass = effil.table()

-- Metamethods
function effil.G._timersContainerClass:__index(key)
    local value = effil.rawget(self, key) -- workaround for effil __index problem in this effil 0.1.0, see #139
    if value ~= nil then
        return value
    end
    return effil.G._timersContainerClass[key]
end

-- Object creation method.
function effil.G._timersContainerClass:new()
    local outer = effil.table()
    effil.setmetatable(outer, self)
    return outer
end

function effil.G._timersContainerClass:getParent()
    return tostring(effil.G._timersContainerClass)
end

Code:

effil = require('effil')

pl = effil.table()

require('timersTEST2')

t = effil.G._timersContainerClass:new()

function checkExpired(t)
    effil = require "effil" -- MUST be global (?)
    print('INSIDE CLASS', effil.G._timersContainerClass) -- OK, xyz as outside
    print('INSIDE PARENT1', effil.G._timersContainerClass:getParent()) -- OK, xyz
    print('INSIDE PARENT2', t:getParent()) -- OK, xyz
end

print('OUTSIDE CLASS', effil.G._timersContainerClass) -- OK, xyz
print('OUTSIDE PARENT1', effil.G._timersContainerClass:getParent()) -- OK, xyz
print('OUTSIDE PARENT2', t:getParent()) -- OK, xyz

effil.sleep(1, 's')

thread = effil.thread(checkExpired)(t)

effil.sleep(1, 's')

thread:status() -- Shows where it failed: in __index while trying t:getParent()

But this is not what I want, since I cannot use effil.G to export the class.
I do not want to export every class I use to every thread I defined, since there are many.

[mihacooper]

Hello, adrfantini!

The problem caused by _G in your function's upvalue again.
You have declared your class global variable:

_timersContainerClass = effil.table()

And after that references it in function:

function _timersContainerClass:getParent()
    return tostring(_timersContainerClass)
end

So, _timersContainerClass:getParent has _G in it's upvalues. But it does not work in Lua, docs here.

To fix the problem you should declare it as a local variable
local _timersContainerClass = effil.table().
And it's better always (where it's possible) do that.

After that you can expose _timersContainerClass like that:
_timersContainerClass = require 'timers' - preferable way (make return _timersContainerClass in your timers module)
Or like that:
_G._timersContainerClass = _timersContainerClass - at the end of 'timers' module. Not really cool, but still works

[adrfantini]

Once again, thank you very much for the time you've taken to dispel my doubts. It's quite clear now!