How to get the calling subclass' name in a superclass' static function?

Question

Suppose we have Check.m:

classdef Check < handle
methods (Static)
    function doStuff()
        if isCalledFromAssertSubclass
            % do this stuff only if called as Assert.doStuff(), not if called as Check.doStuff()
        end
        % do other stuff
    end
end
end

and Assert.m:

classdef Assert < Check
    % nop
end

As written in the comment, I would like to have that Check.doStuff() executes only the "do other stuff" line and that Assert.doStuff() executes the if isCalledFromAssertSubclass block as well.

I want to use static methods, so that I don't neet to create an Assert object whenever I need an assert. Using a global assert object is also very ugly and needs a global assert line in each function I want to use an assert. Likewise for checks.

So there are two problems:

1. Since these are static classes, there is no chance of using class(obj) or any other non-static class property or function.
2. dbstack is not inheritance aware and always returns Check as calling class, also for Assert.doStuff.

I did find a working solution, which uses a combination of dbstack and dbtype to read the line where the call came from, i.e. the line where it says Assert.doStuff(). However it involves two debug functions which probably should not be used in productive code and more importent, dbtype is very slow (in my case, 30 our of 70 seconds!).

I could use a package instead (directory +Check with function files in there) and create a symlink +Assert -> +Check. Then I could check the file name, but that's a) not portable, b) quite ugly and c) also somewhat slow (I suppose).

Is there any faster method for this?

Answer 1

Why not overload the static method for Assert, and have it call the parent's method when it's done? This is the normal way of using inheritance: you don't want the parent, Check, to know anything about its child, Assert.

This is what it would look like:

classdef Assert < Check
methods (Static)
    function doStuff()
        % do some stuff
        Check.doStuff()
    end
end
end

As @Wolfie suggests in a comment, the above works as long as Check.doStuff is not sealed. A sealed method cannot be overloaded. See the documentation.