root/lu/LUProxy.lua

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-- Title:               LUProxy.lua
-- Description:         Like a square peg in a round hole
-- Author:              Raphaël Szwarc http://alt.textdrive.com/lua/
-- Creation Date:       February 1, 2005
-- Legal:               Copyright (C) 2005 Raphaël Szwarc
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-- import dependencies
local LUObject = require( "LUObject" )
local LULog = require( "LULog" )

-- define the class
local super = LUObject
local self = super()

-- class variable(s)
local _forward = {}

-- method for class initialization
function self:initialize()
        super.initialize( self )

        setmetatable( _forward, { __index = _G } )

        self.__index = 
        function( anObject, aKey )
                local aValue = self[ aKey ]
        
                if aValue == nil and aKey:byte( 1 ) ~= 95 then
                        aValue = function( anObject, ... )
                                return anObject:forward( aKey, ... )
                        end
                        
                        setfenv( aValue, _forward )
                end
                
                return aValue
        end
                        
        return self
end

-- method to forward invocations
function self:forward( aMethod, ... )
        error( ( "'%s' does not implement method '%s'" ):format( self:className(), aMethod ) )
end

 -- method to check if this object implements the given method name
function self:respondsTo( aMethod )
        aMethod = self[ aMethod ]
        
        if type( aMethod ) == "function" and getfenv( aMethod ) ~= _forward  then
                return true
        end
        
        return false 
end

return self