RowsAndColumns.hs

Prelude> -- Poor man's row polymorphism
Prelude> data Employee row = Employee { id :: Int, name :: String, otherFields :: row } deriving Show
Prelude> data SalaryInfo = SalaryInfo Int
Prelude> let e = Employee 12 "Rajguru" (SalaryInfo 10000)
Prelude> :t e
e :: Employee SalaryInfo
Prelude>
Prelude> -- Poor man's column polymorphism
Prelude> data AST column = Num Int | Str String | Other column deriving Show
Prelude> let c = Other (SalaryInfo 11)
Prelude> :t c
c :: AST SalaryInfo