Parsec golf.

monad_plus.hs

import qualified Text.Parsec as P
import Control.Applicative
import Control.Monad (msum)

main = do
  P.parseTest primitive0 "short"
  P.parseTest primitive1 "byte"
  P.parseTest primitive2 "char"

primitive0 = do
  P.try (P.string "short")
  <|> P.try (P.string "byte")
  <|> P.try (P.string "char")
  <|> P.try (P.string "long")
  <|> P.try (P.string "int")

keywords = ["short", "byte", "char", "long", "int"]

primitive1 = do
  (foldl1 (<|>) $ map (P.try . P.string) keywords)

primitive2 = do
  msum $ map (P.try . P.string) keywords