Tasteful apps should only perform side-effects through 'window'
arguments rather than the 'curses' module directly. It's ok however to
read constants like curses.A_NORMAL or curses.stdscr().
There are some limitations, unfortunately. Ncurses wasn't designed with
testability in mind. For example, there's no way to curs_set or
assume_default_colors without the 'curses' module. Oh well.
Lua is often not very functional. Available primitives often mutate data
destructively rather than create new values. Perhaps I shouldn't be
trying to go against the grain. We'll see. The above changes are based
on using Teliva intensively for 2 weeks of Advent of Code 2021. But that
isn't quite the ideal use case for Teliva.
Kartik K. Agaram