callLuaFunction method

LuaObject? callLuaFunction(LuaObject obj, { List<Object?> args = const [], })

Given a callable lua obj and a list of args, configure a new scope with the provided args as parameters based on the LuaObject.funcDef record. Args exceeding the parameter list will be dropped. Any remaining parameters will be filled by LuaObject.nil values. Any exceptions are caught and tracked for the trace back later. The scope is popped and any return result LuaObject is returned.

Implementation

LuaObject? callLuaFunction(LuaObject obj, {List<Object?> args = const []}) {
  final metaCall = obj.fieldValueAs<Function>('__call');
  if (metaCall == null) {
    final type = obj.luaTypeInfo;
    final varname = obj.id;
    throw 'Attempt to call a $type value "$varname".';
  }

  LuaObject? res;
  pushScope();
  final defArgs = obj.funcDef!.args;
  final nilCount = defArgs.length - args.length;

  for (int i = 0; i < args.length; i++) {
    final id = defArgs[i].lexeme;
    defLocal(args[i]?.toLua(id) ?? LuaObject.nil(id));
  }

  for (int i = 0; i < nilCount; i++) {
    defLocal(LuaObject.nil(defArgs[args.length + i].lexeme));
  }

  try {
    res = metaCall.call();
  } catch (e) {
    addError(e.toString());
  }
  popScope();

  return res;
}