Makeclass cleaned up

luprex/core/cpp/luastack.cpp

@@ -189,33 +189,17 @@ int LuaStack::next(LuaSlot tab, LuaSlot key, LuaSlot value) const {
     return ret;
 }
 
-bool LuaStack::isemptytable(LuaSlot tab) const {
-    if (lua_istable(L_, tab)) {
-        lua_pushnil(L_);
-        if (lua_next(L_, tab) == 0) {
-            return true;
-        }
-        lua_pop(L_, 2);
-    }
-    return false;
-}
-
 void LuaStack::newtable(LuaSlot target) const {
     lua_newtable(L_);
     lua_replace(L_, target);
 }
 
 void LuaStack::makeclass(LuaSlot classtab, LuaSlot classname) const {
-    int top = lua_gettop(L_);
     checkstring(classname);
 
-    // Special case: if the classname is _G, return global env.
-    lua_pushstring(L_, "_G");
-    int eqlg = lua_equal(L_, -1, classname.index());
-    lua_settop(L_, top);
-    if (eqlg) {
-        set(classtab, LuaGlobals);
-        return;
+    // Special case: if the classname is _G, detect and error.
+    if (equal(classname, "_G")) {
+        luaL_error(L_, "_G is explicitly not allowed as a class name");
     }
     
     // Get the classtab from the global environment.
@@ -236,6 +220,19 @@ void LuaStack::makeclass(LuaSlot classtab, LuaSlot classname) const {
     setfield(classtab, "__class", classname);
 }
 
+void LuaStack::makesubtable(LuaSlot sub, LuaSlot tab, const char *name) const {
+    rawget(sub, tab, name);
+    if (istable(sub)) {
+        return;
+    } else if (isnil(sub)) {
+        newtable(sub);
+        rawset(tab, name, sub);
+        return;
+    } else {
+        luaL_error(L_, "%s is not a table", name);
+    }
+}
+
 void LuaStack::setlightuserdata(LuaSlot target, void *p) const {
     lua_pushlightuserdata(L_, p);
     lua_replace(L_, target);