The best language a program to be written in is the original.

Languages have conventions and best practices that aren’t portable.

We could port COBOL to c and do a crap ton of goto/jmps and make a

     BEGIN MESS

Of course language concepts don't translate.

My point is that one can translate the data flow to another language.

You could imagine any program as input -> [blackbox] -> output. For example, same pixels rendered on the screen provided identical keyboard input.

I propose a way to decompose the blackbox.