redis/deps/lua/test/readonly.lua

-- make global variables readonly

local f=function (t,i) error("cannot redefine global variable `"..i.."'",2) end
local g={}
local G=getfenv()
setmetatable(g,{__index=G,__newindex=f})
setfenv(1,g)

-- an example
rawset(g,"x",3)
x=2
y=1	-- cannot redefine `y'
makefile adapted to link against lua lib and to pass the 32bit flag to Lua building system 2011-04-30 16:15:30 +02:00			`-- make global variables readonly`

			local f=function (t,i) error("cannot redefine global variable `"..i.."'",2) end
			`local g={}`
			`local G=getfenv()`
			`setmetatable(g,{__index=G,__newindex=f})`
			`setfenv(1,g)`

			`-- an example`
			`rawset(g,"x",3)`
			`x=2`
			y=1 -- cannot redefine `y'