Futuruna Playground

# Condition = Sunny | Cloudy | Stormy
# Weather(day: String, temp: Float, condition: Condition)

> describe(w: Weather) -> String {
    match w.condition {
        | Sunny -> show(w.temp) + " C, sunny"
        | Stormy -> show(w.temp) + " C, storm"
        | Cloudy -> show(w.temp) + " C, cloudy"
    }
}

| advisory(w) -> "all clear"
| advisory(w) -> "heat warning" under w.temp > 35.0
| exception storm advisory(w) -> "danger" under w.condition == Stormy

= today = Weather("today", 22.0, Sunny)
= alert = advisory(today)

@ print(today.day + ": " + describe(today) + " -- " + alert)

~ forecast = from_list([today, Weather("tomorrow", 40.0, Sunny), Weather("in 2 days", 18.0, Cloudy), Weather("in 3 days", 10.0, Stormy)]) |> filter(|w| advisory(w) != "all clear")

= warning_count = count(forecast)
| has_warnings: warning_count -> warning_count > 0

? has_warnings: n -> {
    @ print("Upcoming warnings (" + show(n) + "):")
    ~ forecast | w -> {
        @ print("  " + w.day + ": " + advisory(w) + " -> " + describe(w))
    }
} else {
    @ print("No warnings -- all clear ahead")
}