Pretty.hs

{-# OPTIONS_GHC -fno-warn-orphans #-}

-- | A re-export of the prettyprinting library, along with some convenience functions.
module Futhark.Util.Pretty
  ( module Text.PrettyPrint.Mainland,
    module Text.PrettyPrint.Mainland.Class,
    pretty,
    prettyDoc,
    prettyTuple,
    prettyText,
    prettyTextOneLine,
    prettyOneLine,
    apply,
    oneLine,
    annot,
    nestedBlock,
    textwrap,
    shorten,
    commastack,
  )
where

import Data.Text (Text)
import qualified Data.Text.Lazy as LT
import Text.PrettyPrint.Mainland hiding (pretty)
import qualified Text.PrettyPrint.Mainland as PP
import Text.PrettyPrint.Mainland.Class

-- | Prettyprint a value, wrapped to 80 characters.
pretty :: Pretty a => a -> String
pretty = PP.pretty 80 . ppr

-- | Prettyprint a value to a 'Text', wrapped to 80 characters.
prettyText :: Pretty a => a -> Text
prettyText = LT.toStrict . PP.prettyLazyText 80 . ppr

-- | Prettyprint a value to a 'Text' without any width restriction.
prettyTextOneLine :: Pretty a => a -> Text
prettyTextOneLine = LT.toStrict . PP.prettyLazyText 80 . oneLine . ppr

-- | Prettyprint a value without any width restriction.
prettyOneLine :: Pretty a => a -> String
prettyOneLine = ($ "") . displayS . renderCompact . oneLine . ppr

-- | Re-export of 'PP.pretty'.
prettyDoc :: Int -> Doc -> String
prettyDoc = PP.pretty

ppTuple' :: Pretty a => [a] -> Doc
ppTuple' ets = braces $ commasep $ map ppr ets

-- | Prettyprint a list enclosed in curly braces.
prettyTuple :: Pretty a => [a] -> String
prettyTuple = PP.pretty 80 . ppTuple'

-- | The document @'apply' ds@ separates @ds@ with commas and encloses them with
-- parentheses.
apply :: [Doc] -> Doc
apply = parens . commasep . map align

-- | Make sure that the given document is printed on just a single line.
oneLine :: PP.Doc -> PP.Doc
oneLine s = PP.text $ PP.displayS (PP.renderCompact s) ""

-- | Like 'text', but splits the string into words and permits line breaks between all of them.
textwrap :: String -> Doc
textwrap = folddoc (<+/>) . map text . words

-- | Stack and prepend a list of 'Doc's to another 'Doc', separated by
-- a linebreak.  If the list is empty, the second 'Doc' will be
-- returned without a preceding linebreak.
annot :: [Doc] -> Doc -> Doc
annot [] s = s
annot l s = stack l </> s

-- | Surround the given document with enclosers and add linebreaks and
-- indents.
nestedBlock :: String -> String -> Doc -> Doc
nestedBlock pre post body =
  text pre
    </> PP.indent 2 body
    </> text post

-- | Prettyprint on a single line up to at most some appropriate
-- number of characters, with trailing ... if necessary.  Used for
-- error messages.
shorten :: Pretty a => a -> Doc
shorten a
  | length s > 70 = text (take 70 s) <> text "..."
  | otherwise = text s
  where
    s = pretty a

-- | Like 'commasep', but a newline after every comma.
commastack :: [Doc] -> Doc
commastack = align . stack . punctuate comma