content: {-# LANGUAGE CPP, FlexibleInstances, TypeSynonymInstances #-}
  --
  -- Copyright (c) 2005-2022   Stefan Wehr - http://www.stefanwehr.de
  --
  -- This library is free software; you can redistribute it and/or
  -- modify it under the terms of the GNU Lesser General Public
  -- License as published by the Free Software Foundation; either
  -- version 2.1 of the License, or (at your option) any later version.
  --
  -- This library is distributed in the hope that it will be useful,
  -- but WITHOUT ANY WARRANTY; without even the implied warranty of
  -- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  -- Lesser General Public License for more details.
  --
  -- You should have received a copy of the GNU Lesser General Public
  -- License along with this library; if not, write to the Free Software
  -- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA
  --
  
  {- |
  
  This module defines the 'Pretty' type class. The assert functions
  from 'Test.Framework.HUnitWrapper' use the pretty-printing functionality
  provided by this type class so as to provide nicely formatted
  error messages.
  
  Additionally, this module re-exports the standard Haskell pretty-printing module
  'Text.PrettyPrint'
  -}
  module Test.Framework.Pretty (
  
    Pretty(..), (<=>),
  
    module Text.PrettyPrint
  )
  
  where
  
  #if MIN_VERSION_base(4,11,0)
  -- Text.PrettyPrint exports (<>) conflicting with newer Prelude.
  import Text.PrettyPrint hiding ((<>))
  #else
  import Text.PrettyPrint
  #endif
  
  -- | A type class for pretty-printable things.
  -- Minimal complete definition: @pretty@.
  class Pretty a where
      -- | Pretty-print a single value.
      pretty :: a -> Doc
      -- | Pretty-print a list of things.
      prettyList :: [a] -> Doc
      prettyList l =
          char '[' <> vcat (punctuate comma (map pretty l)) <> char ']'
      -- | Pretty-print a single value as a 'String'.
      showPretty :: a -> String
      showPretty = render . pretty
  
  {-
  instance Pretty String where
      pretty = text
  -}
  
  instance Pretty Char where
      pretty = char
      prettyList s = text s
  
  instance Pretty a => Pretty [a] where
      pretty = prettyList
  
  instance Pretty Int where
      pretty = int
  
  instance Pretty Bool where
      pretty = text . show
  
  -- | Utility function for inserting a @=@ between two 'Doc' values.
  (<=>) :: Doc -> Doc -> Doc
  d1 <=> d2 = d1 <+> equals <+> d2
  