+++ /dev/null
---
--- strict.lua
--- checks uses of undeclared global variables
--- All global variables must be 'declared' through a regular assignment
--- (even assigning nil will do) in a main chunk before being used
--- anywhere or assigned to inside a function.
---
-
-local getinfo, error, rawset, rawget = debug.getinfo, error, rawset, rawget
-
-local mt = getmetatable(_G)
-if mt == nil then
- mt = {}
- setmetatable(_G, mt)
-end
-
-__strict = true
-mt.__declared = {}
-
-local function what ()
- local d = getinfo(3, "S")
- return d and d.what or "C"
-end
-
-mt.__newindex = function (t, n, v)
- if __strict and not mt.__declared[n] then
- local w = what()
- if w ~= "main" and w ~= "C" then
- error("assign to undeclared variable '"..n.."'", 2)
- end
- mt.__declared[n] = true
- end
- rawset(t, n, v)
-end
-
-mt.__index = function (t, n)
- if __strict and not mt.__declared[n] and what() ~= "C" then
- error("variable '"..n.."' is not declared", 2)
- end
- return rawget(t, n)
-end
-
-function global(...)
- for _, v in ipairs{...} do mt.__declared[v] = true end
-end