when combing OnCleanup with evalin, weird order of execution

This function is to print in cmd window that the function was executed and exited.

The expected outcome is :

     1
$$$$$$-Entering [testPrologue] 
     2
$$$$$$-Leaving [testPrologue] 

If the fucntion prologue is nested inside the main function, this was true.

However, if I remove the prologue function and make a new file using this fucniton, then print order changed:

     1
$$$$$$-Entering [testPrologue] 
$$$$$$-Leaving [testPrologue] 
     2

Why the "$$$$$$-Leaving" was printed earlier even when "2" has not been printed?

In order to make prologue an independent function, how can I modify it to make it work?

Thanks

function testPrologue
clc;
disp(1);
prologue;
disp(2);
%%
    function prologue
        aStr1 = ['disp(''$$$$$$-Entering testPrologue'');'];
        aStr2 = ['onCleanup(@() disp(''$$$$$$-Leaving [testPrologue]''));'];
        aStr = sprintf('%s\n%s',aStr1,aStr2);
        evalin('caller',aStr);
    end
end