purescript-puchitomato

A small module for a string literal type that guarantees a String value the same as its Symbol parameter.

Usage

appleP = TP.SProxy :: TP.SProxy "apple"

type AppleSL = PT.StringLiteral "apple"

appleSL :: AppleSL
appleSL = PT.mkStringLiteral appleP

main = do
  let (res1 :: JSON.E AppleSL) = JSON.readJSON "\"apple\""
  assert (isRight res1)

  let (res2 :: JSON.E AppleSL) = JSON.readJSON "\"apples\""
  assert (isLeft res2)

  assert (JSON.writeJSON appleSL == "\"apple\"")

  assert (PT.extractString appleSL == "apple")

  assert (show appleSL == "apple")

  let (res4 :: Maybe AppleSL) = PT.parseStringLiteral "apple"
  assert (isJust res4)

  let (res5 :: Maybe AppleSL) = PT.parseStringLiteral "apples"
  assert (isNothing res5)

See the API Docs or the tests for usage.