Variant exaple

Main.purs

module Main where

import Prelude

import Control.Monad.Eff (Eff)
import Control.Monad.Eff.Console (CONSOLE, log)
import Data.Variant (SProxy(SProxy), Variant, inj, match)

oneTwoThree :: Variant (one :: String, two :: Boolean, three :: Number) -> String
oneTwoThree = match {
  one : \a -> a
, two : \b -> show b
, three : \t -> show t
}


main :: forall e. Eff (console :: CONSOLE | e) Unit
main = do
  log $ oneTwoThree (inj (SProxy :: SProxy "one") "Hello, World!")
  log $ oneTwoThree (inj (SProxy :: SProxy "two") true )
  log $ oneTwoThree (inj (SProxy :: SProxy "three") 1.1)