Coupling code

coupled.js

function accountAdd (foo, x) {
  return foo.account + x
}

// accountAdd exhibits stamp coupling and data coupling.

coupled.purs

module Main where

import Prelude

accountAdd foo x = foo.account + x

-- Infered type of accountAdd: forall a r. Semiring a => {account :: a | r} -> a -> a
-- The inferred type represents structural typing with adhoc polymorphism.
-- These forms of typing allow us to be explicit about stamp and data coupling.