I mean, Emacs's oldest source files are like 40 years old at this point, and yes they are in fact legible? I'm not sure what you're asking -- you absolutely can

I mean, Emacs's oldest source files are like 40 years old at this point, and yes they are in fact legible? I'm not sure what you're asking -- you absolutely can (and if you use it long enough, will) read the source code of your text editor.