Use metatables to make gGlobalSoundSource readonly

autogen/lua_constants/built-in.lua

@@ -306,8 +306,20 @@ end
 -- sound --
 -----------
 
+local function read_only(t)
+    local proxy = {}
+    local mt = { -- create metatable
+        __index = t,
+        __newindex = function()
+            error('attempt to update a read-only table', 2)
+        end
+    }
+    setmetatable(proxy, mt)
+    return proxy
+end
+
 --- @type Vec3f
-gGlobalSoundSource = { x = 0, y = 0, z = 0 }
+gGlobalSoundSource = read_only({ x = 0, y = 0, z = 0 })
 
 --- @param bank number
 --- @param soundID number

autogen/lua_definitions/constants.lua

@@ -308,8 +308,20 @@ end
 -- sound --
 -----------
 
+local function read_only(t)
+    local proxy = {}
+    local mt = { -- create metatable
+        __index = t,
+        __newindex = function()
+            error('attempt to update a read-only table', 2)
+        end
+    }
+    setmetatable(proxy, mt)
+    return proxy
+end
+
 --- @type Vec3f
-gGlobalSoundSource = { x = 0, y = 0, z = 0 }
+gGlobalSoundSource = read_only({ x = 0, y = 0, z = 0 })
 
 --- @param bank number
 --- @param soundID number

src/pc/lua/smlua_constants_autogen.c

@@ -272,8 +272,19 @@ char gSmluaConstants[] = ""
 "-----------\n"
 "-- sound --\n"
 "-----------\n"
+"local function read_only(t)\n"
+"    local proxy = {}\n"
+"    local mt = { -- create metatable\n"
+"        __index = t,\n"
+"        __newindex = function()\n"
+"            error('attempt to update a read-only table', 2)\n"
+"        end\n"
+"    }\n"
+"    setmetatable(proxy, mt)\n"
+"    return proxy\n"
+"end\n"
 "--- @type Vec3f\n"
-"gGlobalSoundSource = { x = 0, y = 0, z = 0 }\n"
+"gGlobalSoundSource = read_only({ x = 0, y = 0, z = 0 })\n"
 "--- @param bank number\n"
 "--- @param soundID number\n"
 "--- @param priority number\n"