# clock/index.ludic - the clock needs the time of day and asks for it through a port: it names
# no module that answers, so it `uses` only units
module clock uses units
export port Clock {
  now: fn() -> int
  day: fn() -> int = fn first_day
}
function first_day() -> int {
  return 1
}
export function hour_of_day() -> int {
  return Clock.now() - (Clock.day() - 1) * HOURS
}