The terminal is keystroke-driven. It's character-selectable. It's reliable in a way that the GUI is not. When I drop frames, I can still enter the commands to rescue myself with some assurance they'll be interpreted, eventually.
I agree, a REPL isn't Unixy in the streams of text kind of way... or is it?
I agree, a REPL isn't Unixy in the streams of text kind of way... or is it?