compiler/AST/PrettyPrint.hs · elk

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elk/compiler/AST/PrettyPrint.hs

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1{-# LANGUAGE FlexibleInstances #-}

2module AST.PrettyPrint where

4import Control.Monad.Trans.Error

5import Text.PrettyPrint as P

6import qualified AST.Helpers as Help

8class Pretty a where

9 pretty :: a -> Doc

11instance Pretty Doc where

12 pretty doc = doc

14instance Pretty String where

15 pretty = P.text

17renderPretty :: (Pretty a) => a -> String

18renderPretty e = render (pretty e)

20commaCat docs = cat (punctuate comma docs)

21commaSep docs = sep (punctuate comma docs)

23parensIf :: Bool -> Doc -> Doc

24parensIf bool doc = if bool then parens doc else doc

26variable :: String -> Doc

27variable x =

28 if Help.isOp x then parens (text x) else text x

30eightyCharLines :: Int -> String -> String

31eightyCharLines indent message = answer

32 where

33 (answer,_,_) = foldl step (spaces, indent-1, "") chunks

35 chunks = map (\w -> (w, length w)) (words message)

36 spaces = replicate indent ' '

37 step (sentence, slen, space) (word, wlen)

38 | slen + wlen > 79 = (sentence ++ "\n" ++ spaces ++ word, indent + wlen, " ")

39 | otherwise = (sentence ++ space ++ word, slen + wlen + length space, " ")

41instance ErrorList Doc where

42 listMsg str = [ P.text str ]