compiler/SourceSyntax/PrettyPrint.hs · elk

on 2f8b048 help sign in

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1{-# LANGUAGE FlexibleInstances #-}

2module SourceSyntax.PrettyPrint where

4import Text.PrettyPrint as P

5import qualified SourceSyntax.Helpers as Help

7class Pretty a where

8 pretty :: a -> Doc

10instance Pretty Doc where

11 pretty doc = doc

13instance Pretty String where

14 pretty = P.text

16renderPretty :: (Pretty a) => a -> String

17renderPretty e = render (pretty e)

19commaCat docs = cat (punctuate comma docs)

20commaSep docs = sep (punctuate comma docs)

22parensIf :: Bool -> Doc -> Doc

23parensIf bool doc = if bool then parens doc else doc

25variable :: String -> Doc

26variable x =

27 if Help.isOp x then parens (text x)

28 else text (reprime x)

30reprime :: String -> String

31reprime = map (\c -> if c == '$' then '\'' else c)

33eightyCharLines :: Int -> String -> String

34eightyCharLines indent message = answer

35 where

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

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

39 spaces = replicate indent ' '

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

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

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