No way to know whenever the readModel method in DnnSuperRes has worked

When i use the the readModel method of DnnSuperRes i have no way to know whenever it has worked, i.e. the file exists, the format is correct, the weights are read.
In the whole DnnSuperRes class there is no method that returns something useful for it.
The readNet method of dnn class returns instead a Net object that, in case of uncorrect weights, is empty.
More generally, in my C++ software i would like to avoid an exception when the user chooses an uncorrect file, but i would like to have a simple warning.