compound-types-0.1.2: demo/Main.hs

module Main where

import Rebase.Prelude
import CompoundTypes.Strict


main =
  putStrLn "This demonstration is all about the compilability"

-- |
-- This function exhibits the benefit of the first-class sum-type
-- being usable as a function parameter.
-- 
-- It also shows, how we can pattern-match it.
intCharBoolSumToString :: Int + Char + Bool -> String
intCharBoolSumToString =
  \case
    Sum3_1 int -> "Int: " <> show int
    Sum3_2 char -> "Char: " <> show char
    Sum3_3 bool -> "Bool: " <> show bool

-- |
-- Following is an example of a more complicated composition,
-- which is the same as the following type:
-- 
-- > Sum3 Int (Product2 Char (Sum2 Bool String)) Char
-- 
-- Just as in the math, the product operator exhibits a higher priority.
type SumAndProductMixture =
  Int + Char * (Bool + String) + Char