wl-pprint-extras-3.5.0.5/0000755000000000000000000000000012535672361013322 5ustar0000000000000000wl-pprint-extras-3.5.0.5/.travis.yml0000644000000000000000000000034512535672361015435 0ustar0000000000000000language: haskell notifications: irc: channels: - "irc.freenode.org#haskell-lens" skip_join: true template: - "\x0313wl-pprint-extras\x03/\x0306%{branch}\x03 \x0314%{commit}\x03 %{build_url} %{message}" wl-pprint-extras-3.5.0.5/LICENSE0000644000000000000000000000247412535672361014336 0ustar0000000000000000Portions Copyright 2013, Google, Inc. Copyright 2011, Edward Kmett Copyright 2000, Daan Leijen All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. This software is provided by the copyright holders "as is" and any express or implied warranties, including, but not limited to, the implied warranties of merchantability and fitness for a particular purpose are disclaimed. In no event shall the copyright holders be liable for any direct, indirect, incidental, special, exemplary, or consequential damages (including, but not limited to, procurement of substitute goods or services; loss of use, data, or profits; or business interruption) however caused and on any theory of liability, whether in contract, strict liability, or tort (including negligence or otherwise) arising in any way out of the use of this software, even if advised of the possibility of such damage. wl-pprint-extras-3.5.0.5/Setup.lhs0000644000000000000000000000011412535672361015126 0ustar0000000000000000#!/usr/bin/env runhaskell > import Distribution.Simple > main = defaultMain wl-pprint-extras-3.5.0.5/wl-pprint-extras.cabal0000644000000000000000000000264612535672361017556 0ustar0000000000000000name: wl-pprint-extras category: Control, Monads, Text version: 3.5.0.5 cabal-version: >= 1.8 license: BSD3 license-file: LICENSE author: Edward A. Kmett maintainer: Edward A. Kmett stability: experimental homepage: http://github.com/ekmett/wl-pprint-extras/ bug-reports: http://github.com/ekmett/wl-pprint-extras/issues copyright: Copyright (C) 2011-2012 Edward A. Kmett, Copyright (C) 2000 Daan Leijen synopsis: A free monad based on the Wadler/Leijen pretty printer description: A free monad based on the Wadler/Leijen pretty printer build-type: Simple extra-source-files: .travis.yml source-repository head type: git location: git://github.com/ekmett/wl-pprint-extras.git library build-depends: base == 4.*, containers >= 0.4 && < 0.6, nats >= 0.1 && < 2, semigroups >= 0.9 && < 1, semigroupoids >= 3 && < 6, utf8-string >= 0.3.6 && < 1.1, text >= 0.11 && < 1.3 exposed-modules: Text.PrettyPrint.Free Text.PrettyPrint.Free.Internal ghc-options: -Wall hs-source-dirs: src test-suite wl-pprint-tests build-depends: base == 4.*, wl-pprint-extras, HUnit, test-framework, test-framework-hunit main-is: WLPPrintTests.hs type: exitcode-stdio-1.0 ghc-options: -Wall hs-source-dirs: test wl-pprint-extras-3.5.0.5/src/0000755000000000000000000000000012535672361014111 5ustar0000000000000000wl-pprint-extras-3.5.0.5/src/Text/0000755000000000000000000000000012535672361015035 5ustar0000000000000000wl-pprint-extras-3.5.0.5/src/Text/PrettyPrint/0000755000000000000000000000000012535672361017341 5ustar0000000000000000wl-pprint-extras-3.5.0.5/src/Text/PrettyPrint/Free.hs0000644000000000000000000001002712535672361020556 0ustar0000000000000000{-# OPTIONS_GHC -fno-warn-incomplete-patterns #-} ----------------------------------------------------------------------------- -- | -- Module : Text.PrettyPrint.Free -- Copyright : Google, Inc. (c) 2013, -- Edward Kmett (c) 2011, -- Daan Leijen (c) 2000 -- License : BSD-style (see the file LICENSE) -- -- Maintainer : ekmett@gmail.com -- Stability : experimental -- Portability : portable -- -- Pretty print module based on Daan Leijen's implementation of Philip Wadler's -- \"prettier printer\" -- -- @ -- \"A prettier printer\" -- Draft paper, April 1997, revised March 1998. -- -- @ -- -- This is an implementation of the pretty printing combinators -- described by Philip Wadler (1997). In their bare essence, the -- combinators of Wadler are not expressive enough to describe some -- commonly occurring layouts. The PPrint library adds new primitives -- to describe these layouts and works well in practice. -- -- The library is based on a single way to concatenate documents, -- which is associative and has both a left and right unit. This -- simple design leads to an efficient and short implementation. The -- simplicity is reflected in the predictable behaviour of the -- combinators which make them easy to use in practice. -- -- A thorough description of the primitive combinators and their -- implementation can be found in Philip Wadler's paper -- (1997). Additions and the main differences with his original paper -- are: -- -- * The nil document is called empty. -- -- * The operator '' is used -- for soft line breaks. -- -- * There are three new primitives: 'align', 'fill' and -- 'fillBreak'. These are very useful in practice. -- -- * Lots of other useful combinators, like 'fillSep' and 'list'. -- -- * There are two renderers, 'renderPretty' for pretty printing and -- 'renderCompact' for compact output. The pretty printing algorithm -- also uses a ribbon-width now for even prettier output. -- -- * There are two displayers, 'displayS' for strings and 'displayIO' for -- file based output. -- -- * There is a 'Pretty' class. -- -- * The implementation uses optimised representations and strictness -- annotations. -- -- * A type argument has been added and embedded 'effects' can be seen in -- the SimpleDoc type. -- -- ----------------------------------------------------------- module Text.PrettyPrint.Free ( -- * Documents Doc, putDoc, hPutDoc -- * Basic combinators , char, text, nest, line, linebreak, group, softline , softbreak, hardline, flatAlt, flatten -- * Alignment -- -- The combinators in this section can not be described by Wadler's -- original combinators. They align their output relative to the -- current output position - in contrast to @nest@ which always -- aligns to the current nesting level. This deprives these -- combinators from being \`optimal\'. In practice however they -- prove to be very useful. The combinators in this section should -- be used with care, since they are more expensive than the other -- combinators. For example, @align@ shouldn't be used to pretty -- print all top-level declarations of a language, but using @hang@ -- for let expressions is fine. , align, hang, indent, encloseSep, list, tupled, semiBraces -- * Operators , (<+>), above, (), aboveBreak, () -- * List combinators , hsep, vsep, fillSep, sep, hcat, vcat, fillCat, cat, punctuate -- * Fillers , fill, fillBreak -- * Bracketing combinators , enclose, squotes, dquotes, parens, angles, braces, brackets -- * Character documents , lparen, rparen, langle, rangle, lbrace, rbrace, lbracket, rbracket , squote, dquote, semi, colon, comma, space, dot, backslash, equals -- * Pretty class , Pretty(..) -- * Rendering , SimpleDoc(..), renderPretty, renderCompact, renderSmart , displayS, displayIO -- * Undocumented , column, nesting, width, columns -- * Re-exported standard functions , empty, (<>) ) where import Text.PrettyPrint.Free.Internal wl-pprint-extras-3.5.0.5/src/Text/PrettyPrint/Free/0000755000000000000000000000000012535672361020222 5ustar0000000000000000wl-pprint-extras-3.5.0.5/src/Text/PrettyPrint/Free/Internal.hs0000644000000000000000000011441612535672361022341 0ustar0000000000000000----------------------------------------------------------------------------- -- | -- Module : Text.PrettyPrint.Free.Internal -- Copyright : Google, Inc. (c) 2013, -- Edward Kmett (c) 2011, -- Daan Leijen (c) 2000 -- -- License : BSD-style (see the file LICENSE) -- -- Maintainer : ekmett@gmail.com -- Stability : experimental -- Portability : portable -- -- Pretty print module based on Daan Leijen's implementation of Philip Wadler's -- \"prettier printer\" -- -- @ -- \"A prettier printer\" -- Draft paper, April 1997, revised March 1998. -- -- @ -- -- This is an implementation of the pretty printing combinators -- described by Philip Wadler (1997). In their bare essence, the -- combinators of Wadler are not expressive enough to describe some -- commonly occurring layouts. The PPrint library adds new primitives -- to describe these layouts and works well in practice. -- -- The library is based on a single way to concatenate documents, -- which is associative and has both a left and right unit. This -- simple design leads to an efficient and short implementation. The -- simplicity is reflected in the predictable behaviour of the -- combinators which make them easy to use in practice. -- -- A thorough description of the primitive combinators and their -- implementation can be found in Philip Wadler's paper -- (1997). Additions and the main differences with his original paper -- are: -- -- * The nil document is called empty. -- -- * The operator '' is used -- for soft line breaks. -- -- * There are three new primitives: 'align', 'fill' and -- 'fillBreak'. These are very useful in practice. -- -- * Lots of other useful combinators, like 'fillSep' and 'list'. -- -- * There are two renderers, 'renderPretty' for pretty printing and -- 'renderCompact' for compact output. The pretty printing algorithm -- also uses a ribbon-width now for even prettier output. -- -- * There are two display routines, 'displayS' for strings and 'displayIO' -- for file based output. -- -- * There is a 'Pretty' class. -- -- * The implementation uses optimised representations and strictness -- annotations. -- -- * A type argument has been added and embedded 'effects' can be seen in -- the SimpleDoc type. -- -- ----------------------------------------------------------- module Text.PrettyPrint.Free.Internal ( -- * Documents Doc(..), putDoc, hPutDoc -- * Basic combinators , char, text, nest, line, linebreak, group, softline , softbreak, hardline, flatAlt, flatten -- * Alignment -- -- The combinators in this section can not be described by Wadler's -- original combinators. They align their output relative to the -- current output position - in contrast to @nest@ which always -- aligns to the current nesting level. This deprives these -- combinators from being \`optimal\'. In practice however they -- prove to be very useful. The combinators in this section should -- be used with care, since they are more expensive than the other -- combinators. For example, @align@ shouldn't be used to pretty -- print all top-level declarations of a language, but using @hang@ -- for let expressions is fine. , align, hang, indent, encloseSep, list, tupled, semiBraces -- * Operators , (<+>), above, (), aboveBreak, () -- * List combinators , hsep, vsep, fillSep, sep, hcat, vcat, fillCat, cat, punctuate -- * Fillers , fill, fillBreak -- * Bracketing combinators , enclose, squotes, dquotes, parens, angles, braces, brackets -- * Character documents , lparen, rparen, langle, rangle, lbrace, rbrace, lbracket, rbracket , squote, dquote, semi, colon, comma, space, dot, backslash, equals -- * Pretty class , Pretty(..) -- * Rendering , SimpleDoc(..), renderPretty, renderCompact, renderSmart , displayS, displayIO -- * Undocumented , column, nesting, width, columns, ribbon -- * Re-exported standard functions , empty, (<>) ) where import Data.String import Data.Foldable hiding (fold) import Data.Traversable import Data.Functor.Apply import Data.Functor.Bind import Data.Functor.Plus import Data.Int import Data.Word import qualified Data.ByteString.UTF8 as B import qualified Data.ByteString.Lazy.UTF8 as BL import qualified Data.Text as T import qualified Data.Text.Encoding as T import qualified Data.Text.Lazy as TL import qualified Data.Text.Lazy.Encoding as TL import Data.List.NonEmpty (NonEmpty) import Numeric.Natural (Natural) import Control.Applicative import Control.Monad import Data.Sequence (Seq) import Data.Semigroup import System.IO (Handle,hPutStr,hPutChar,stdout) import Prelude hiding (foldr1) infixr 5 ,,`above`,`aboveBreak` infixr 6 <+> ----------------------------------------------------------- -- list, tupled and semiBraces pretty print a list of -- documents either horizontally or vertically aligned. ----------------------------------------------------------- -- | The document @(list xs)@ comma separates the documents @xs@ and -- encloses them in square brackets. The documents are rendered -- horizontally if that fits the page. Otherwise they are aligned -- vertically. All comma separators are put in front of the elements. list :: Foldable f => f (Doc e) -> Doc e list = encloseSep lbracket rbracket comma -- | The document @(tupled xs)@ comma separates the documents @xs@ and -- encloses them in parenthesis. The documents are rendered -- horizontally if that fits the page. Otherwise they are aligned -- vertically. All comma separators are put in front of the elements. tupled :: Foldable f => f (Doc e) -> Doc e tupled = encloseSep lparen rparen comma (<+>) :: Doc e -> Doc e -> Doc e x <+> y = x <> space <> y -- | The document @(semiBraces xs)@ separates the documents @xs@ with -- semi colons and encloses them in braces. The documents are rendered -- horizontally if that fits the page. Otherwise they are aligned -- vertically. All semi colons are put in front of the elements. semiBraces :: Foldable f => f (Doc e) -> Doc e semiBraces = encloseSep lbrace rbrace semi -- | The document @(encloseSep l r sep xs)@ concatenates the documents -- @xs@ separated by @sep@ and encloses the resulting document by @l@ -- and @r@. The documents are rendered horizontally if that fits the -- page. Otherwise they are aligned vertically. All separators are put -- in front of the elements. For example, the combinator 'list' can be -- defined with @encloseSep@: -- -- > list xs = encloseSep lbracket rbracket comma xs -- > test = text "list" <+> (list (map int [10,200,3000])) -- -- Which is layed out with a page width of 20 as: -- -- @ -- list [10, 200, 3000] -- @ -- -- But when the page width is 15, it is layed out as: -- -- @ -- list [ 10 -- , 200 -- , 3000 ] -- @ encloseSep :: Foldable f => Doc e -> Doc e -> Doc e -> f (Doc e) -> Doc e encloseSep left right sp ds0 = case toList ds0 of [] -> left <> right [d] -> left <> d <> right ds -> group $ align $ left' <> (vcat (zipWith (<>) (empty : repeat (sp <> space)) ds)) <> right' where left' = left <> flatAlt space empty right' = flatAlt space empty <> right ----------------------------------------------------------- -- punctuate p [d1,d2,...,dn] => [d1 <> p,d2 <> p, ... ,dn] ----------------------------------------------------------- -- | @(punctuate p xs)@ concatenates all documents in @xs@ with -- document @p@ except for the last document. -- -- > someText = map text ["words","in","a","tuple"] -- > test = parens (align (cat (punctuate comma someText))) -- -- This is layed out on a page width of 20 as: -- -- @ -- (words,in,a,tuple) -- @ -- -- But when the page width is 15, it is layed out as: -- -- @ -- (words, -- in, -- a, -- tuple) -- @ -- -- (If you want put the commas in front of their elements instead of -- at the end, you should use 'tupled' or, in general, 'encloseSep'.) punctuate :: Traversable f => Doc e -> f (Doc e) -> f (Doc e) punctuate p xs = snd $ mapAccumL (\(d:ds) _ -> (ds, if null ds then d else (d <> p))) (toList xs) xs ----------------------------------------------------------- -- high-level combinators ----------------------------------------------------------- -- | The document @(sep xs)@ concatenates all documents @xs@ either -- horizontally with @(\<+\>)@, if it fits the page, or vertically with -- @above@. -- -- > sep xs = group (vsep xs) sep :: Foldable f => f (Doc e) -> Doc e sep = group . vsep -- | The document @(fillSep xs)@ concatenates documents @xs@ -- horizontally with @(\<+\>)@ as long as its fits the page, then -- inserts a @line@ and continues doing that for all documents in -- @xs@. -- -- > fillSep xs = foldr () empty xs fillSep :: Foldable f => f (Doc e) -> Doc e fillSep = fold () -- | The document @(hsep xs)@ concatenates all documents @xs@ -- horizontally with @(\<+\>)@. hsep :: Foldable f => f (Doc e) -> Doc e hsep = fold (<+>) -- | The document @(vsep xs)@ concatenates all documents @xs@ -- vertically with @above@. If a 'group' undoes the line breaks -- inserted by @vsep@, all documents are separated with a space. -- -- > someText = map text (words ("text to lay out")) -- > -- > test = text "some" <+> vsep someText -- -- This is layed out as: -- -- @ -- some text -- to -- lay -- out -- @ -- -- The 'align' combinator can be used to align the documents under -- their first element -- -- > test = text "some" <+> align (vsep someText) -- -- Which is printed as: -- -- @ -- some text -- to -- lay -- out -- @ vsep :: Foldable f => f (Doc e) -> Doc e vsep = fold above -- | The document @(cat xs)@ concatenates all documents @xs@ either -- horizontally with @(\<\>)@, if it fits the page, or vertically with -- @aboveBreak@. -- -- > cat xs = group (vcat xs) cat :: Foldable f => f (Doc e) -> Doc e cat = group . vcat -- | The document @(fillCat xs)@ concatenates documents @xs@ -- horizontally with @(\<\>)@ as long as its fits the page, then inserts -- a @linebreak@ and continues doing that for all documents in @xs@. -- -- > fillCat xs = foldr () empty xs fillCat :: Foldable f => f (Doc e) -> Doc e fillCat = fold () -- | The document @(hcat xs)@ concatenates all documents @xs@ -- horizontally with @(\<\>)@. hcat :: Foldable f => f (Doc e) -> Doc e hcat = fold (<>) -- | The document @(vcat xs)@ concatenates all documents @xs@ -- vertically with @aboveBreak@. If a 'group' undoes the line breaks -- inserted by @vcat@, all documents are directly concatenated. vcat :: Foldable f => f (Doc e) -> Doc e vcat = fold aboveBreak fold :: Foldable f => (Doc e -> Doc e -> Doc e) -> f (Doc e) -> Doc e fold f xs = case toList xs of [] -> empty _ -> foldr1 f xs instance Semigroup (Doc e) where -- | The document @(x \<\> y)@ concatenates document @x@ and document -- @y@. It is an associative operation having 'empty' as a left and -- right unit. (infixl 6) (<>) = Cat instance Monoid (Doc e) where mappend = Cat mempty = empty -- | The document @(x \<\/\> y)@ concatenates document @x@ and @y@ with a -- 'softline' in between. This effectively puts @x@ and @y@ either -- next to each other (with a @space@ in between) or underneath each -- other. (infixr 5) () :: Doc e -> Doc e -> Doc e x y = x <> softline <> y -- | The document @(x \<\/\/\> y)@ concatenates document @x@ and @y@ with -- a 'softbreak' in between. This effectively puts @x@ and @y@ either -- right next to each other or underneath each other. (infixr 5) () :: Doc e -> Doc e -> Doc e x y = x <> softbreak <> y -- | The document @above x y@ concatenates document @x@ and @y@ with a -- 'line' in between. (infixr 5) above :: Doc e -> Doc e -> Doc e above x y = x <> line <> y -- | The document @aboveBreak x y@ concatenates document @x@ and @y@ with -- a @linebreak@ in between. (infixr 5) aboveBreak :: Doc e -> Doc e -> Doc e aboveBreak x y = x <> linebreak <> y -- | The document @softline@ behaves like 'space' if the resulting -- output fits the page, otherwise it behaves like 'line'. -- -- > softline = group line softline :: Doc e softline = group line -- | The document @softbreak@ behaves like 'empty' if the resulting -- output fits the page, otherwise it behaves like 'line'. -- -- > softbreak = group linebreak softbreak :: Doc e softbreak = group linebreak -- | Document @(squotes x)@ encloses document @x@ with single quotes -- \"'\". squotes :: Doc e -> Doc e squotes = enclose squote squote -- | Document @(dquotes x)@ encloses document @x@ with double quotes -- '\"'. dquotes :: Doc e -> Doc e dquotes = enclose dquote dquote -- | Document @(braces x)@ encloses document @x@ in braces, \"{\" and -- \"}\". braces :: Doc e -> Doc e braces = enclose lbrace rbrace -- | Document @(parens x)@ encloses document @x@ in parenthesis, \"(\" -- and \")\". parens :: Doc e -> Doc e parens = enclose lparen rparen -- | Document @(angles x)@ encloses document @x@ in angles, \"\<\" and -- \"\>\". angles :: Doc e -> Doc e angles = enclose langle rangle -- | Document @(brackets x)@ encloses document @x@ in square brackets, -- \"[\" and \"]\". brackets :: Doc e -> Doc e brackets = enclose lbracket rbracket -- | The document @(enclose l r x)@ encloses document @x@ between -- documents @l@ and @r@ using @(\<\>)@. -- -- > enclose l r x = l <> x <> r enclose :: Doc e -> Doc e -> Doc e -> Doc e enclose l r x = l <> x <> r -- | The document @lparen@ contains a left parenthesis, \"(\". lparen :: Doc e lparen = char '(' -- | The document @rparen@ contains a right parenthesis, \")\". rparen :: Doc e rparen = char ')' -- | The document @langle@ contains a left angle, \"\<\". langle :: Doc e langle = char '<' -- | The document @rangle@ contains a right angle, \">\". rangle :: Doc e rangle = char '>' -- | The document @lbrace@ contains a left brace, \"{\". lbrace :: Doc e lbrace = char '{' -- | The document @rbrace@ contains a right brace, \"}\". rbrace :: Doc e rbrace = char '}' -- | The document @lbracket@ contains a left square bracket, \"[\". lbracket :: Doc e lbracket = char '[' -- | The document @rbracket@ contains a right square bracket, \"]\". rbracket :: Doc e rbracket = char ']' -- | The document @squote@ contains a single quote, \"'\". squote :: Doc e squote = char '\'' -- | The document @dquote@ contains a double quote, '\"'. dquote :: Doc e dquote = char '"' -- | The document @semi@ contains a semi colon, \";\". semi :: Doc e semi = char ';' -- | The document @colon@ contains a colon, \":\". colon :: Doc e colon = char ':' -- | The document @comma@ contains a comma, \",\". comma :: Doc e comma = char ',' -- | The document @space@ contains a single space, \" \". -- -- > x <+> y = x <> space <> y space :: Doc e space = char ' ' -- | The document @dot@ contains a single dot, \".\". dot :: Doc e dot = char '.' -- | The document @backslash@ contains a back slash, \"\\\". backslash :: Doc e backslash = char '\\' -- | The document @equals@ contains an equal sign, \"=\". equals :: Doc e equals = char '=' instance IsString (Doc e) where fromString = pretty ----------------------------------------------------------- -- overloading "pretty" ----------------------------------------------------------- -- | The member @prettyList@ is only used to define the @instance Pretty -- a => Pretty [a]@. In normal circumstances only the @pretty@ function -- is used. class Pretty a where pretty :: a -> Doc e prettyList :: [a] -> Doc e prettyList = list . map pretty instance Pretty a => Pretty [a] where pretty = prettyList -- instance Pretty (Doc ()) where -- pretty = id instance Pretty B.ByteString where pretty = pretty . B.toString instance Pretty BL.ByteString where pretty = pretty . BL.toString instance Pretty T.Text where pretty = pretty . T.encodeUtf8 instance Pretty TL.Text where pretty = pretty . TL.encodeUtf8 instance Pretty () where pretty () = text "()" instance Pretty Bool where pretty = text . show instance Pretty Char where pretty = char prettyList "" = empty prettyList ('\n':s) = line <> prettyList s prettyList s = case span (/='\n') s of (xs,ys) -> text xs <> prettyList ys instance Pretty a => Pretty (Seq a) where pretty = prettyList . toList instance Pretty a => Pretty (NonEmpty a) where pretty = prettyList . toList instance Pretty Int where pretty = text . show instance Pretty Int8 where pretty = text . show instance Pretty Int16 where pretty = text . show instance Pretty Int32 where pretty = text . show instance Pretty Int64 where pretty = text . show instance Pretty Word where pretty = text . show instance Pretty Word8 where pretty = text . show instance Pretty Word16 where pretty = text . show instance Pretty Word32 where pretty = text . show instance Pretty Word64 where pretty = text . show instance Pretty Integer where pretty = text . show instance Pretty Natural where pretty = text . show instance Pretty Float where pretty = text . show instance Pretty Double where pretty = text . show instance Pretty (Doc a) where pretty d = d *> empty instance (Pretty a,Pretty b) => Pretty (a,b) where pretty (x,y) = tupled [pretty x, pretty y] instance (Pretty a,Pretty b,Pretty c) => Pretty (a,b,c) where pretty (x,y,z)= tupled [pretty x, pretty y, pretty z] instance Pretty a => Pretty (Maybe a) where pretty Nothing = empty pretty (Just x) = pretty x ----------------------------------------------------------- -- semi primitive: fill and fillBreak ----------------------------------------------------------- -- | The document @(fillBreak i x)@ first renders document @x@. It -- then appends @space@s until the width is equal to @i@. If the -- width of @x@ is already larger than @i@, the nesting level is -- increased by @i@ and a @line@ is appended. When we redefine @ptype@ -- in the previous example to use @fillBreak@, we get a useful -- variation of the previous output: -- -- > ptype (name,tp) -- > = fillBreak 6 (text name) <+> text "::" <+> text tp -- -- The output will now be: -- -- @ -- let empty :: Doc e -- nest :: Int -> Doc e -> Doc e -- linebreak -- :: Doc e -- @ fillBreak :: Int -> Doc e -> Doc e fillBreak f x = width x $ \w -> if (w > f) then nest f linebreak else text (spaces (f - w)) -- | The document @(fill i x)@ renders document @x@. It then appends -- @space@s until the width is equal to @i@. If the width of @x@ is -- already larger, nothing is appended. This combinator is quite -- useful in practice to output a list of bindings. The following -- example demonstrates this. -- -- > types = [("empty","Doc e") -- > ,("nest","Int -> Doc e -> Doc e") -- > ,("linebreak","Doc e")] -- > -- > ptype (name,tp) -- > = fill 6 (text name) <+> text "::" <+> text tp -- > -- > test = text "let" <+> align (vcat (map ptype types)) -- -- Which is layed out as: -- -- @ -- let empty :: Doc e -- nest :: Int -> Doc e -> Doc e -- linebreak :: Doc e -- @ fill :: Int -> Doc e -> Doc e fill f d = width d $ \w -> if (w >= f) then empty else text (spaces (f - w)) width :: Doc e -> (Int -> Doc e) -> Doc e width d f = column (\k1 -> d <> column (\k2 -> f (k2 - k1))) ----------------------------------------------------------- -- semi primitive: Alignment and indentation ----------------------------------------------------------- -- | The document @(indent i x)@ indents document @x@ with @i@ spaces. -- -- > test = indent 4 (fillSep (map text -- > (words "the indent combinator indents these words !"))) -- -- Which lays out with a page width of 20 as: -- -- @ -- the indent -- combinator -- indents these -- words ! -- @ indent :: Int -> Doc e -> Doc e indent i d = hang i (text (spaces i) <> d) -- | The hang combinator implements hanging indentation. The document -- @(hang i x)@ renders document @x@ with a nesting level set to the -- current column plus @i@. The following example uses hanging -- indentation for some text: -- -- > test = hang 4 (fillSep (map text -- > (words "the hang combinator indents these words !"))) -- -- Which lays out on a page with a width of 20 characters as: -- -- @ -- the hang combinator -- indents these -- words ! -- @ -- -- The @hang@ combinator is implemented as: -- -- > hang i x = align (nest i x) hang :: Int -> Doc e -> Doc e hang i d = align (nest i d) -- | The document @(align x)@ renders document @x@ with the nesting -- level set to the current column. It is used for example to -- implement 'hang'. -- -- As an example, we will put a document right above another one, -- regardless of the current nesting level: -- -- > x $$ y = align (above x y) -- -- > test = text "hi" <+> (text "nice" $$ text "world") -- -- which will be layed out as: -- -- @ -- hi nice -- world -- @ align :: Doc e -> Doc e align d = column $ \k -> nesting $ \i -> nest (k - i) d --nesting might be negative :-) ----------------------------------------------------------- -- Primitives ----------------------------------------------------------- -- | The abstract data type @Doc@ represents pretty documents. -- -- @Doc@ is an instance of the 'Show' class. @(show doc)@ pretty -- prints document @doc@ with a page width of 100 characters and a -- ribbon width of 40 characters. -- -- > show (text "hello" `above` text "world") -- -- Which would return the string \"hello\\nworld\", i.e. -- -- @ -- hello -- world -- @ data Doc e = Fail | Empty | Char {-# UNPACK #-} !Char -- invariant: char is not '\n' | Text {-# UNPACK #-} !Int String -- invariant: text doesn't contain '\n' | Line | FlatAlt (Doc e) (Doc e) -- Render the first doc, but when flattened, render the second. | Cat (Doc e) (Doc e) | Nest {-# UNPACK #-} !Int (Doc e) | Union (Doc e) (Doc e) -- invariant: first lines of first doc longer than the first lines of the second doc | Effect e | Column (Int -> Doc e) | Nesting (Int -> Doc e) | Columns (Int -> Doc e) | Ribbon (Int -> Doc e) instance Functor Doc where fmap _ Fail = Fail fmap _ Empty = Empty fmap _ (Char c) = Char c fmap _ Line = Line fmap _ (Text i s) = Text i s fmap f (FlatAlt l r) = FlatAlt (fmap f l) (fmap f r) fmap f (Cat l r) = Cat (fmap f l) (fmap f r) fmap f (Nest i d) = Nest i (fmap f d) fmap f (Union l r) = Union (fmap f l) (fmap f r) fmap f (Effect e) = Effect (f e) fmap f (Column k) = Column (fmap f . k) fmap f (Nesting k) = Nesting (fmap f . k) fmap f (Columns k) = Columns (fmap f . k) fmap f (Ribbon k) = Columns (fmap f . k) instance Apply Doc where (<.>) = ap instance Applicative Doc where pure = Effect (<*>) = ap instance Bind Doc where (>>-) = (>>=) instance Monad Doc where return = Effect Fail >>= _ = Fail Empty >>= _ = Empty Char c >>= _ = Char c Text i s >>= _ = Text i s Line >>= _ = Line FlatAlt l r >>= k = FlatAlt (l >>= k) (r >>= k) Cat l r >>= k = Cat (l >>= k) (r >>= k) Nest i d >>= k = Nest i (d >>= k) Union l r >>= k = Union (l >>= k) (r >>= k) Effect e >>= k = k e Column f >>= k = Column (f >=> k) Nesting f >>= k = Nesting (f >=> k) Columns f >>= k = Columns (f >=> k) Ribbon f >>= k = Ribbon (f >=> k) fail _ = empty instance Alt Doc where () = (<>) instance Plus Doc where zero = empty instance Alternative Doc where (<|>) = (<>) -- | The empty document is, indeed, empty. Although @empty@ has no -- content, it does have a \'height\' of 1 and behaves exactly like -- @(text \"\")@ (and is therefore not a unit of @above@). empty = Empty instance MonadPlus Doc where mplus = (<>) mzero = empty -- | The data type @SimpleDoc@ represents rendered documents and is -- used by the display functions. -- -- The @Int@ in @SText@ contains the length of the string. The @Int@ -- in @SLine@ contains the indentation for that line. The library -- provides two default display functions 'displayS' and -- 'displayIO'. You can provide your own display function by writing a -- function from a @SimpleDoc@ to your own output format. data SimpleDoc e = SFail | SEmpty | SChar {-# UNPACK #-} !Char (SimpleDoc e) | SText {-# UNPACK #-} !Int String (SimpleDoc e) | SLine {-# UNPACK #-} !Int (SimpleDoc e) | SEffect e (SimpleDoc e) instance Functor SimpleDoc where fmap _ SFail = SFail fmap _ SEmpty = SEmpty fmap f (SChar c d) = SChar c (fmap f d) fmap f (SText i s d) = SText i s (fmap f d) fmap f (SLine i d) = SLine i (fmap f d) fmap f (SEffect e d) = SEffect (f e) (fmap f d) instance Foldable SimpleDoc where foldMap _ SFail = mempty foldMap _ SEmpty = mempty foldMap f (SChar _ d) = foldMap f d foldMap f (SText _ _ d) = foldMap f d foldMap f (SLine _ d) = foldMap f d foldMap f (SEffect e d) = f e `mappend` foldMap f d instance Traversable SimpleDoc where traverse _ SFail = pure SFail traverse _ SEmpty = pure SEmpty traverse f (SChar c d) = SChar c <$> traverse f d traverse f (SText i s d) = SText i s <$> traverse f d traverse f (SLine i d) = SLine i <$> traverse f d traverse f (SEffect e d) = SEffect <$> f e <*> traverse f d -- | The document @(char c)@ contains the literal character @c@. The -- character shouldn't be a newline (@'\n'@), the function 'line' -- should be used for line breaks. char :: Char -> Doc e char '\n' = line char c = Char c -- | The document @(text s)@ contains the literal string @s@. The -- string shouldn't contain any newline (@'\n'@) characters. If the -- string contains newline characters, the function 'string' should be -- used. text :: String -> Doc e text "" = Empty text s = Text (length s) s -- | The @line@ document advances to the next line and indents to the -- current nesting level. Document @line@ behaves like @(text \" \")@ -- if the line break is undone by 'group'. line :: Doc e line = FlatAlt Line space -- | The @linebreak@ document advances to the next line and indents to -- the current nesting level. Document @linebreak@ behaves like -- 'empty' if the line break is undone by 'group'. linebreak :: Doc e linebreak = FlatAlt Line empty -- | A linebreak that can not be flattened; it is guaranteed to be -- rendered as a newline. hardline :: Doc e hardline = Line -- | The document @(nest i x)@ renders document @x@ with the current -- indentation level increased by i (See also 'hang', 'align' and -- 'indent'). -- -- > nest 2 (text "hello" `above` text "world") `above` text "!" -- -- outputs as: -- -- @ -- hello -- world -- ! -- @ nest :: Int -> Doc e -> Doc e nest = Nest column, nesting :: (Int -> Doc e) -> Doc e column = Column nesting = Nesting columns :: (Int -> Doc e) -> Doc e columns = Columns ribbon :: (Int -> Doc e) -> Doc e ribbon = Ribbon -- | The @group@ combinator is used to specify alternative -- layouts. The document @(group x)@ undoes all line breaks in -- document @x@. The resulting line is added to the current line if -- that fits the page. Otherwise, the document @x@ is rendered without -- any changes. group :: Doc e -> Doc e group x = Union (flatten x) x -- | @flatAlt@ creates a document that changes when flattened; normally -- it is rendered as the first argument, but when flattened is rendered -- as the second. flatAlt :: Doc e -> Doc e -> Doc e flatAlt = FlatAlt flatten :: Doc e -> Doc e flatten (FlatAlt _ y) = y flatten (Cat x y) = Cat (flatten x) (flatten y) flatten (Nest i x) = Nest i (flatten x) flatten Line = Fail flatten (Union x _) = flatten x flatten (Column f) = Column (flatten . f) flatten (Nesting f) = Nesting (flatten . f) flatten (Columns f) = Columns (flatten . f) flatten (Ribbon f) = Ribbon (flatten . f) flatten other = other --Empty,Char,Text ----------------------------------------------------------- -- Renderers ----------------------------------------------------------- ----------------------------------------------------------- -- renderPretty: the default pretty printing algorithm ----------------------------------------------------------- -- list of indentation/document pairs; saves an indirection over [(Int,Doc)] data Docs e = Nil | Cons {-# UNPACK #-} !Int (Doc e) (Docs e) -- | This is the default pretty printer which is used by 'show', -- 'putDoc' and 'hPutDoc'. @(renderPretty ribbonfrac width x)@ renders -- document @x@ with a page width of @width@ and a ribbon width of -- @(ribbonfrac * width)@ characters. The ribbon width is the maximal -- amount of non-indentation characters on a line. The parameter -- @ribbonfrac@ should be between @0.0@ and @1.0@. If it is lower or -- higher, the ribbon width will be 0 or @width@ respectively. renderPretty :: Float -> Int -> Doc e -> SimpleDoc e renderPretty = renderFits nicest1 -- | A slightly smarter rendering algorithm with more lookahead. It provides -- provide earlier breaking on deeply nested structures. -- For example, consider this python-ish pseudocode: -- @fun(fun(fun(fun(fun([abcdefg, abcdefg])))))@ -- If we put a softbreak (+ nesting 2) after each open parenthesis, and align -- the elements of the list to match the opening brackets, this will render with -- @renderPretty@ and a page width of 20c as: -- @ -- fun(fun(fun(fun(fun([ -- | abcdef, -- | abcdef, -- ] -- ))))) | -- @ -- Where the 20c. boundary has been marked with |. Because @renderPretty@ only -- uses one-line lookahead, it sees that the first line fits, and is stuck -- putting the second and third lines after the 20c mark. In contrast, -- @renderSmart@ will continue to check the potential document up to the end of -- the indentation level. Thus, it will format the document as: -- -- @ -- fun( | -- fun( | -- fun( | -- fun( | -- fun([ | -- abcdef, -- abcdef, -- ] | -- ))))) | -- @ -- Which fits within the 20c. mark. -- In addition, @renderSmart@ uses this lookahead to minimize the number of -- lines printed, leading to more compact and visually appealing output. -- Consider this example using the same syntax as above: -- @aaaaaaaaaaa([abc, def, ghi])@ -- When rendered with @renderPretty@ and a page width of 20c, we get: -- @ -- aaaaaaaaaaa([ abc -- , def -- , ghi ]) -- @ -- Whereas when rendered with @renderSmart@ and a page width of 20c, we get: -- @ -- aaaaaaaaaaa( -- [abc, def, ghi]) -- @ renderSmart :: Int -> Doc e -> SimpleDoc e renderSmart = renderFits nicestR 1.0 renderFits :: (Int -> Int -> Int -> Int -> SimpleDoc e -> SimpleDoc e -> SimpleDoc e) -> Float -> Int -> Doc e -> SimpleDoc e renderFits nicest rfrac w x = best 0 0 (Cons 0 x Nil) where -- r :: the ribbon width in characters r = max 0 (min w (round (fromIntegral w * rfrac))) -- best :: n = indentation of current line -- k = current column -- (ie. (k >= n) && (k - n == count of inserted characters) best _ _ Nil = SEmpty best n k (Cons i d ds) = case d of Fail -> SFail Empty -> best n k ds Char c -> let k' = k+1 in seq k' (SChar c (best n k' ds)) Text l s -> let k' = k+l in seq k' (SText l s (best n k' ds)) Line -> SLine i (best i i ds) FlatAlt l _ -> best n k (Cons i l ds) Cat x' y -> best n k (Cons i x' (Cons i y ds)) Nest j x' -> let i' = i+j in seq i' (best n k (Cons i' x' ds)) Effect e -> SEffect e (best n k ds) Union p q -> nicest n k w r (best n k (Cons i p ds)) (best n k (Cons i q ds)) Column f -> best n k (Cons i (f k) ds) Nesting f -> best n k (Cons i (f i) ds) Columns f -> best n k (Cons i (f w) ds) Ribbon f -> best n k (Cons i (f r) ds) -- @nicest1@ compares the first lines of the two documents. -- n = nesting, k = column, p = pagewidth nicest1 :: Int -> Int -> Int -> Int -> SimpleDoc e -> SimpleDoc e -> SimpleDoc e nicest1 n k p r x' y | fits (min n k) wid x' = x' | otherwise = y where wid = min (p - k) (r - k + n) fits _ w _ | w < 0 = False fits _ _ SFail = False fits _ _ SEmpty = True fits m w (SChar _ x) = fits m (w - 1) x fits m w (SText l _ x) = fits m (w - l) x fits _ _ (SLine _ _) = True fits m w (SEffect _ x) = fits m w x -- @nicestR@ compares the initial lines of the two documents that are nested at -- least as deep as the current nesting level. If the initial lines of both -- documents fit within the page width, the document that takes fewer lines is -- prefered, with preference toward the first. nicestR :: Int -> Int -> Int -> Int -> SimpleDoc e -> SimpleDoc e -> SimpleDoc e nicestR n k p r x' y = if fits (min n k) wid x' <= fits (min n k) wid y then x' else y where wid = min (p - k) (r - k + n) inf = 1.0/0 :: Double -- @fitsR@ has a little more lookahead: assuming that nesting roughly -- corresponds to syntactic depth, @fitsR@ checks that not only the -- current line fits, but the entire syntactic structure being formatted -- at this level of indentation fits. If we were to remove the second -- case for @SLine@, we would check that not only the current structure -- fits, but also the rest of the document, which would be slightly more -- intelligent but would have exponential runtime (and is prohibitively -- expensive in practice). -- m = minimum nesting level to fit in -- w = the width in which to fit the first line fits _ w _ | w < 0 = inf fits _ _ SFail = inf fits _ _ SEmpty = 0 fits m w (SChar _ x) = fits m (w - 1) x fits m w (SText l _ x) = fits m (w - l) x fits m _ (SLine i x) | m < i = 1 + fits m (p - i) x | otherwise = 0 fits m w (SEffect _ x) = fits m w x ----------------------------------------------------------- -- renderCompact: renders documents without indentation -- fast and fewer characters output, good for machines ----------------------------------------------------------- -- | @(renderCompact x)@ renders document @x@ without adding any -- indentation. Since no \'pretty\' printing is involved, this -- renderer is very fast. The resulting output contains fewer -- characters than a pretty printed version and can be used for output -- that is read by other programs. renderCompact :: Doc e -> SimpleDoc e renderCompact x = scan 0 [x] where scan _ [] = SEmpty scan k (d:ds) = case d of Fail -> SFail Empty -> scan k ds Char c -> let k' = k+1 in seq k' (SChar c (scan k' ds)) Text l s -> let k' = k+l in seq k' (SText l s (scan k' ds)) Effect e -> SEffect e (scan k ds) Line -> SLine 0 (scan 0 ds) FlatAlt y _ -> scan k (y:ds) Cat y z -> scan k (y:z:ds) Nest _ y -> scan k (y:ds) Union _ y -> scan k (y:ds) Column f -> scan k (f k:ds) Nesting f -> scan k (f 0:ds) Columns f -> scan k (f 80:ds) Ribbon f -> scan k (f 80:ds) ----------------------------------------------------------- -- Displayers: displayS and displayIO ----------------------------------------------------------- -- | @(displayS simpleDoc)@ takes the output @simpleDoc@ from a -- rendering function and transforms it to a 'ShowS' type (for use in -- the 'Show' class). -- -- > showWidth :: Int -> Doc -> String -- > showWidth w x = displayS (renderPretty 0.4 w x) "" displayS :: SimpleDoc e -> ShowS displayS SFail = error $ "@SFail@ can not appear uncaught in a " ++ "rendered @SimpleDoc@" displayS SEmpty = id displayS (SChar c x) = showChar c . displayS x displayS (SText _ s x) = showString s . displayS x displayS (SLine i x) = showString ('\n':indentation i) . displayS x displayS (SEffect _ t) = displayS t -- | @(displayIO handle simpleDoc)@ writes @simpleDoc@ to the file -- handle @handle@. This function is used for example by 'hPutDoc': -- -- > hPutDoc handle doc = displayIO handle (renderPretty 0.4 100 doc) displayIO :: Handle -> SimpleDoc e -> IO () displayIO handle = go where go SFail = error $ "@SFail@ can not appear uncaught in a " ++ "rendered @SimpleDoc@" go SEmpty = return () go (SChar c x) = hPutChar handle c >> go x go (SText _ s x) = hPutStr handle s >> go x go (SLine i x) = hPutStr handle ('\n':indentation i) >> go x go (SEffect _ t) = go t ----------------------------------------------------------- -- default pretty printers: show, putDoc and hPutDoc ----------------------------------------------------------- instance Show (Doc e) where showsPrec _ doc = displayS (renderPretty 0.4 80 doc) -- | The action @(putDoc doc)@ pretty prints document @doc@ to the -- standard output, with a page width of 100 characters and a ribbon -- width of 40 characters. -- -- > main :: IO () -- > main = do{ putDoc (text "hello" <+> text "world") } -- -- Which would output -- -- @ -- hello world -- @ putDoc :: Doc e -> IO () putDoc doc = hPutDoc stdout doc -- | @(hPutDoc handle doc)@ pretty prints document @doc@ to the file -- handle @handle@ with a page width of 100 characters and a ribbon -- width of 40 characters. -- -- > main = do{ handle <- openFile "MyFile" WriteMode -- > ; hPutDoc handle (vcat (map text -- > ["vertical","text"])) -- > ; hClose handle -- > } hPutDoc :: Handle -> Doc e -> IO () hPutDoc handle doc = displayIO handle (renderPretty 0.4 80 doc) ----------------------------------------------------------- -- insert spaces -- "indentation" used to insert tabs but tabs seem to cause -- more trouble than they solve :-) ----------------------------------------------------------- spaces :: Int -> String spaces n | n <= 0 = "" | otherwise = replicate n ' ' indentation :: Int -> String indentation n = spaces n --indentation n | n >= 8 = '\t' : indentation (n-8) -- | otherwise = spaces n -- LocalWords: PPrint combinators Wadler Wadler's encloseSep wl-pprint-extras-3.5.0.5/test/0000755000000000000000000000000012535672361014301 5ustar0000000000000000wl-pprint-extras-3.5.0.5/test/WLPPrintTests.hs0000644000000000000000000002377512535672361017355 0ustar0000000000000000module Main where import Test.Framework import Test.Framework.Providers.HUnit import Test.HUnit hiding (Test) import Text.PrettyPrint.Free.Internal main :: IO () main = defaultMain [ testGroup "Tests for each data constructor" conTests , testGroup "Tests for some combinators" codeTests , testGroup "Tests for the formatting algorithms" formatTests , testGroup "Tests for the code examples in the documentation" docTests ] conTests :: [Test] conTests = [ testCase "Empty tests" emptyTests , testCase "Char tests" charTests , testCase "Text tests" textTests , testCase "Line tests" textTests , testCase "FlatAlt tests" flatAltTests , testCase "Cat tests" catTests , testCase "Nest tests" nestTests , testCase "Union tests" unionTests , testCase "Column tests" columnTests , testCase "Nesting tests" nestingTests , testCase "Columns tests" columnsTests , testCase "Ribbon tests" ribbonTests ] ------------------------------------------------------------ -- We test the @Doc@ constructors. assertPretty :: Int -> String -> String -> Doc e -> Assertion assertPretty w desc str doc = assertEqual (desc ++ " (pretty)") str $ displayS (renderPretty 1.0 w doc) "" assertSmart :: Int -> String -> String -> Doc e -> Assertion assertSmart w desc str doc = assertEqual (desc ++ " (smart)") str $ displayS (renderSmart w doc) "" assertRender :: Int -> String -> String -> Doc e -> Assertion assertRender w desc str doc = do assertPretty w desc str doc assertSmart w desc str doc emptyTests :: Assertion emptyTests = assertRender 80 "Empty test 1" "" empty charTests :: Assertion charTests = assertRender 80 "Char test 1" "a" (char 'a') textTests :: Assertion textTests = assertRender 80 "Text test 1" "text..." (text "text...") lineTests :: Assertion lineTests = assertRender 80 "Line test 1" "\n" hardline flatAltTests :: Assertion flatAltTests = do assertRender 80 "FlatAlt test 1" "x" $ flatAlt (text "x") (text "y") assertRender 80 "FlatAlt test 2" "y" $ flatten $ flatAlt (text "x") (text "y") catTests :: Assertion catTests = do assertRender 80 "Cat test 1" "some code" $ text "some" <> space <> text "code" nestTests :: Assertion nestTests = do assertRender 80 "Nest test 1" "foo bar" $ text "foo" <+> nest 2 (text "bar") assertRender 80 "Nest test 2" "foo\n bar" $ text "foo" <> nest 2 (line <> text "bar") unionTests :: Assertion unionTests = do assertRender 80 "Union test 1" "foo bar" $ text "foo" text "bar" assertRender 5 "Union test 2" "foo\nbar" $ text "foo" text "bar" columnTests :: Assertion columnTests = do assertRender 80 "Column test 1" "foo 4" $ text "foo" <+> (column $ \c -> pretty c) nestingTests :: Assertion nestingTests = do assertRender 80 "Nesting test 1" "foo 2" $ text "foo" <+> (nest 2 $ nesting $ \n -> pretty n) columnsTests :: Assertion columnsTests = do assertRender 21 "Columns test 1" "foo 21" $ text "foo" <+> (nest 2 $ columns $ \w -> pretty w) ribbonTests :: Assertion ribbonTests = do assertEqual "Ribbon test 1" "foo 32" $ show (text "foo" <+> (ribbon $ \r -> pretty r)) ------------------------------------------------------------ -- We test some combinators. codeTests :: [Test] codeTests = [ testCase "@list@ tests" listTests , testCase "@tupled@ tests" tupledTests ] listTests :: Assertion listTests = do assertRender 80 "@list@ test 1" "[1, 2, 3]" $ pretty ([1, 2, 3] :: [Int]) assertRender 5 "@list@ test 2" "[ 1\n, 2\n, 3 ]" $ pretty ([1, 2, 3] :: [Int]) tupledTests :: Assertion tupledTests = do assertRender 80 "@tupled@ test 1" "(1, True, a)" $ pretty (1 :: Int, True, 'a') assertRender 5 "@tupled@ test 2" "( 1\n, True\n, a )" $ pretty (1 :: Int, True, 'a') ------------------------------------------------------------ -- We test some corner cases of the formatting algorithms on a prototypical -- syntax for a scripting language (e.g. Python). formatTests :: [Test] formatTests = [ testCase "@renderPretty@ test" renderPrettyTest , testCase "@renderSmart@ test" renderSmartTest ] data Syn = Call String [Syn] -- name(syn, ..., syn) | Plus Syn Syn -- syn + syn | List [Syn] -- [syn, ..., syn] | Name String instance Pretty Syn where pretty (Call n s) = text (n ++ "(") <> nest 2 (softbreak <> align body) rparen where body = hcat $ punctuate (comma <> softline) (map pretty s) pretty (Plus s t) = nest 2 (pretty s) text "+" nest 2 (pretty t) pretty (List l) = list (map pretty l) pretty (Name n) = text n deep :: Int -> Syn deep 0 = List (map Name ["abc", "abcdef", "abcdef"]) deep i = Call "fun" [deep (i - 1)] branch :: Int -> Syn branch 0 = List (map Name ["abc", "abc"]) branch i | i < 3 = Call "fun" [branch (i - 1), branch (i - 1)] | otherwise = Call "fun" [branch (i - 1)] wide :: Syn wide = Call "aaaaaaaaaaa" [List $ map Name ["abc", "def", "ghi"]] -- @renderPretty@ has only one line of lookahead, so it can not fit the -- entire document within the pagewidth (20c), only the first line. renderPrettyTest :: Assertion renderPrettyTest = do assertPretty 20 "@renderPretty@ test 1" (concat [ "fun(fun(fun(fun(fun(\n" , " [ abc\n" , " , abcdef\n" , " , abcdef ]\n" , " ))))\n" , ")" ]) $ pretty (deep 5) assertPretty 20 "@renderPretty@ test 2" (concat [ "fun(fun(fun([ abc\n" , " , abc ],\n" , " [ abc\n" , " , abc ]\n" , " ), fun([ abc\n" , " , abc ],\n" , " [ abc\n" , " , abc ]\n" , " )))" ]) $ pretty (branch 3) assertPretty 20 "@renderPretty@ test 3" (concat [ "aaaaaaaaaaa([ abc\n" , " , def\n" , " , ghi ])" ]) $ pretty wide -- @renderSmart@ has more sophisiticated lookahead, so it fits the entire -- structure within the pagewidth (20c). renderSmartTest :: Assertion renderSmartTest = do assertSmart 20 "@renderSmart@ test 1" (concat [ "fun(\n" , " fun(\n" , " fun(\n" , " fun(\n" , " fun(\n" , " [ abc\n" , " , abcdef\n" , " , abcdef ]\n" , " )))))" ]) $ pretty (deep 5) assertSmart 20 "@renderSmart@ test 2" (concat [ "fun(\n" , " fun(\n" , " fun(\n" , " fun(\n" , " fun([ abc\n" , " , abc ],\n" , " [ abc\n" , " , abc ]\n" , " ),\n" , " fun([ abc\n" , " , abc ],\n" , " [ abc\n" , " , abc ])\n" , " ))))" ]) $ pretty (branch 5) assertSmart 20 "@renderSmart@ test 3" (concat [ "aaaaaaaaaaa(\n" , " [abc, def, ghi])" ]) $ pretty wide ------------------------------------------------------------ -- We test the code examples in the haddock comments. docTests :: [Test] docTests = [ testCase "@fill@ test" fillTest , testCase "@fillBreak@ test" fillBreakTest , testCase "@hang@ test" hangTest , testCase "@align@ test" alignTest ] types :: [(String, String)] types = [ ("empty","Doc e") , ("nest","Int -> Doc e -> Doc e") , ("linebreak","Doc e") ] fillTest :: Assertion fillTest = do assertRender 80 "@fill@ test 1" (concat [ "let empty :: Doc e\n" , " nest :: Int -> Doc e -> Doc e\n" , " linebreak :: Doc e" ]) $ text "let" <+> align (vcat (map ptype types)) where ptype (name, tp) = fill 6 (text name) <+> text "::" <+> text tp fillBreakTest :: Assertion fillBreakTest = do assertRender 80 "@fillBreak@ test 1" (concat [ "let empty :: Doc e\n" , " nest :: Int -> Doc e -> Doc e\n" , " linebreak\n" , " :: Doc e" ]) $ text "let" <+> align (vcat (map ptype types)) where ptype (name, tp) = fillBreak 6 (text name) <+> (text "::" <+> text tp) hangTest :: Assertion hangTest = do assertRender 20 "@hang@ test 1" (concat [ "the hang combinator\n" , " indents these\n" , " words !" ]) $ hang 4 $ fillSep $ map text $ words "the hang combinator indents these words !" alignTest :: Assertion alignTest = do assertRender 20 "@align@ test 1" (concat [ "hi nice\n" , " world" ]) $ text "hi" <+> (text "nice" $$ text "world") where x $$ y = align $ x <> linebreak <> y