RowPolymorphism.ps

module Main where

import Prelude

type Student = {
              first :: String,
              last :: String,
              class :: String
            }

type GymMember = {
              first :: String,
              last :: String,
              benchPressPB :: Int
            }

daveG :: GymMember
daveG = {
        first: "Dave",
        last: "Bro",
        benchPressPB: 300
    }

philS :: Student
philS = {
        first : "Dave",
        last : "Swat",
        class : "1A"
      }

type NamedThing t =
                { last :: String
                , first :: String
                | t
                }

schoolRollName :: forall t. NamedThing t -> String
schoolRollName rec = rec.last <> ", " <> rec.first

firstAndSurname :: forall t. NamedThing t -> String
firstAndSurname rec =  rec.first <> " " <> rec.last

daveFandS :: String
daveFandS = firstAndSurname daveG

daveSR :: String
daveSR = schoolRollName daveG

philFandS :: String
philFandS = firstAndSurname philS

philSR :: String
philSR = schoolRollName philS