TryPureScript.org example

Main.purs

module Main where

import Prelude

import Data.Codec.Argonaut as CA
import Data.Codec.Argonaut (JsonDecodeError)
import Data.Codec.Argonaut.Record as CAR
import Data.Codec.Argonaut.Common as CAC
import Data.Argonaut.Parser as AP
import Data.Argonaut.Core as AC
import Data.Argonaut.Core (Json)
import Data.Either
import Data.Maybe
import Data.Time.Duration
import Effect
import Effect.Class
import Effect.Aff
import Effect.Aff as Aff
import Effect.Aff.Class
import Effect.Class.Console (log, logShow)
import TryPureScript (render, withConsole)

transform :: Json -> Either JsonDecodeError String
transform = CA.decode CA.string

type Person = { name :: String, age :: Number }

main :: Effect Unit
main = render =<< withConsole do
  
  ------------
  -- | Values
  ------------
  let
    person = { person: { name: "Alice McBob", age: 42.69 } }
    
    personCodec =
      CAR.object "PERSON"
        { person: CAR.object "PERSON inner" { name: CA.string, age: CA.number}
        }
    
    encodedPerson = AC.stringify (CA.encode personCodec person) :: String

  ---------
  -- | I/O
  ---------
  heading "PERSON"
  logShow person
  
  heading "PERSON encoded as Json"
  logShow encodedPerson
  
  heading "PARSING & RE-DECODING PERSON"  
  case AP.jsonParser encodedPerson of
    Left error1 -> log error1
    Right json ->
      case CA.decode personCodec json of
        Left error2 -> log $ CA.printJsonDecodeError error2
        Right person' -> logShow person'

----------------------------------------
-- | Stuff
----------------------------------------
heading :: forall m. MonadEffect m => String -> m Unit
heading txt = log $ "\n=== " <> txt <> "===\n"

withLabel :: forall m. MonadEffect m => String -> String -> m Unit
withLabel label txt = log $ "[ " <> label <> " ] " <> txt

delay :: String -> Number -> Aff Unit
delay label secs = do
  withLabel label $ "Delaying " <> show secs <> " seconds"
  Aff.delay (convertDuration $ Seconds secs)
  withLabel label $ "Delay of " <> show secs <> " seconds complete!"