Always true validtor in haskell

always_true.hs

{-# LANGUAGE DataKinds           #-}
{-# LANGUAGE ImportQualifiedPost #-}
{-# LANGUAGE NoImplicitPrelude   #-}
{-# LANGUAGE OverloadedStrings   #-}
{-# LANGUAGE TemplateHaskell     #-}

module FortyTwo where

import qualified Plutus.V2.Ledger.Api as PlutusV2
import           PlutusTx             (BuiltinData, compile)
import           PlutusTx.Builtins    as Builtins (mkI)
import           PlutusTx.Prelude     (otherwise, traceError, (==))
import           Prelude              (IO)
import           Utilities            (writeValidatorToFile)

---------------------------------------------------------------------------------------------------
----------------------------------- ON-CHAIN / VALIDATOR ------------------------------------------

-- This validator succeeds only if the redeemer is 42
--                  Datum         Redeemer     ScriptContext
mk42Validator :: BuiltinData -> BuiltinData -> BuiltinData -> ()
mk42Validator _ r _
    | r == Builtins.mkI 42 = ()
    | otherwise            = traceError "expected 42"
{-# INLINABLE mk42Validator #-}

validator :: PlutusV2.Validator
validator = PlutusV2.mkValidatorScript $$(PlutusTx.compile [|| mk42Validator ||])

---------------------------------------------------------------------------------------------------
------------------------------------- HELPER FUNCTIONS --------------------------------------------

saveVal :: IO ()
saveVal = writeValidatorToFile "./assets/fortytwo.plutus" validator