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Table Freezing

Tables can now be frozen at their current state to forbid any future modification. This action is irreversible and permanent for the lifespan of the table.

Example Code 1
-- Disallowing any edits to the global environment table.table.freeze(_G)_G.string = {}-- file.pluto:2: attempt to modify frozen table.
Example Code 2
-- Creating a constant local that's associated with a frozen table.local Frozen <const> = table.freeze({ 1, 2, 3 })Frozen = {}-- file.pluto:4: attempt to reassign constant.Frozen[1] = "new value"-- file.pluto:7: attempt to modify frozen table.rawset(Frozen, "key", "value")-- file.pluto:10: attempt to modify frozen table.
Example Code 3
--- Trying to swap the value with the debug library.for i = 1, 249 do  local name, value = debug.getlocal(1, i)  if name == "Frozen" then    debug.setlocal(1, i, { ["key"] = "hello world" })    -- file.pluto:5: attempt to modify local variable with a frozen table.  endend

What will this prevent?​

All modifications to the table from within the Lua environment will be prevented, including those from the debug library.

caution

If you're going to use this for a sandbox, ensure you call table.freeze before any users can access the Lua environment, otherwise they can replace that function.