Module:No globals: Difference between revisions

    From Nonbinary Wiki
    m>Jackmcbarn
    (Created page with 'local mt = getmetatable(_G) or {} local oldIndex = mt.__index or function() return nil end mt.__index = function(t, k) if k ~= 'name' and k ~= 'arg' then erro...')
     
    m (4 revisions imported from wikipedia:Module:No_globals: see Topic:Vtixlm0q28eo6jtf)
     
    (20 intermediate revisions by 16 users not shown)
    Line 1: Line 1:
    local mt = getmetatable(_G) or {}
    local mt = getmetatable(_G) or {}
    local oldIndex = mt.__index or function() return nil end
    function mt.__index (t, k)
    mt.__index = function(t, k)
    if k ~= 'arg' then
    if k ~= 'name' and k ~= 'arg' then
    error('Tried to read nil global ' .. tostring(k), 2)
    error('Tried to read nil global ' .. tostring(k), 2)
    end
    end
    return oldIndex(t, k)
    return nil
    end
    end
    local oldNewindex = mt.__newindex or rawset
    function mt.__newindex(t, k, v)
    function mt.__newindex(t, k, v)
    if k ~= 'name' and k ~= 'arg' then
    if k ~= 'arg' then
    error('Tried to write global ' .. tostring(k), 2)
    error('Tried to write global ' .. tostring(k), 2)
    end
    end
    oldNewindex(t, k, v)
    rawset(t, k, v)
    end
    end
    setmetatable(_G, mt)
    setmetatable(_G, mt)

    Latest revision as of 11:43, 21 May 2021

    Documentation for this module may be created at Module:No globals/doc

    local mt = getmetatable(_G) or {}
    function mt.__index (t, k)
    	if k ~= 'arg' then
    		error('Tried to read nil global ' .. tostring(k), 2)
    	end
    	return nil
    end
    function mt.__newindex(t, k, v)
    	if k ~= 'arg' then
    		error('Tried to write global ' .. tostring(k), 2)
    	end
    	rawset(t, k, v)
    end
    setmetatable(_G, mt)