Lua OOP Class Module

local Module_classExtension = {}

function Module_classExtension.addParentClass(Class_targetClass,Class_newClass)

    table.insert(getmetatable(Class_targetClass).__index._proxy,Class_newClass)

    --[[
    insert Class_newClass into the table with _proxy in it. _proxy contains the parent classes
    ]]

end

function Module_classExtension.removeParentClass(Class_targetClass,Class_classToRemove)

    local Tab_proxyTable = getmetatable(Class_targetClass).__index._proxy
    for Int_giPosition,Class_parentClass in pairs(Tab_proxyTable) do
        if Class_parentClass == Class_classToRemove then
            table.remove(Tab_proxyTable,Int_giPosition)
        end
    end

    --[[
    get the _proxy table
    iterate through the proxy table, and
    if the class in the proxy table is the class we need to remove then
    remove it
    ]]

end

function Module_classExtension.findMethodFromParentClasses(Tab_proxyTable,Func_method)

    for Int_giIndex,Class_gvClass in pairs(Tab_proxyTable._proxy) do
        if Class_gvClass[Func_method] then
            return Class_gvClass[Func_method]
        end
    end

    --[[
    iterate through _proxy in Tab_proxyTable,
    if one of the classes has the method then
    return the method
    ]]

end

function Module_classExtension.getParentClasses(Class_targetClass)

    return getmetatable(Class_targetClass).__index._proxy

    --[[
    return the the classes in _proxy
    ]]

end

function Module_classExtension.createMultipleInheritance(Class_baseClass)

    setmetatable(Class_baseClass,{__index = setmetatable({_proxy = {}},{__index = Module_classExtension.findMethodFromParentClasses})})

    --[[
    this allows multiple inheritance
    the structure is:
    Class ==_index==> {_proxy = {parent1,parent2,...}} ==_index==> function findMethodFromParentClasses
    ]]

end



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local Class_drawing = {}

function Class_drawing:newShape(String_name)
    return {["String_shape"] = String_name}
end

function Class_drawing:drawShape()
    print(self["String_shape"])
end

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local Class_quadrilateral = {}
Module_classExtension.createMultipleInheritance(Class_quadrilateral)
Module_classExtension.addParentClass(Class_quadrilateral,Class_drawing)

function Class_quadrilateral:someMethod()
    print("HI")
end


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local Class_square = {}
Module_classExtension.createMultipleInheritance(Class_square)
Module_classExtension.addParentClass(Class_square,Class_quadrilateral)

function Class_square:newSquare()
    return setmetatable(self:newShape("Square"),{__index = self})
end


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local Square_newSquare = Class_square:newSquare()
Square_newSquare:drawShape()
Square_newSquare:someMethod()