wl-pprint-text-1.1.0.4/0000755000000000000000000000000012510475415012763 5ustar0000000000000000wl-pprint-text-1.1.0.4/LICENSE0000644000000000000000000000300312510475415013764 0ustar0000000000000000Copyright (c)2010, Ivan Lazar Miljenovic 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. * Neither the name of Ivan Lazar Miljenovic nor the names of other contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 OWNER OR CONTRIBUTORS 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-text-1.1.0.4/Setup.hs0000644000000000000000000000005612510475415014420 0ustar0000000000000000import Distribution.Simple main = defaultMain wl-pprint-text-1.1.0.4/wl-pprint-text.cabal0000644000000000000000000000144112510475415016665 0ustar0000000000000000Name: wl-pprint-text Version: 1.1.0.4 Synopsis: A Wadler/Leijen Pretty Printer for Text values Description: A clone of wl-pprint for use with the text library. License: BSD3 License-file: LICENSE Author: Ivan Lazar Miljenovic Maintainer: Ivan.Miljenovic@gmail.com Copyright: 2007 Daan Leijen, 2010 Ivan Lazar Miljenovic Category: Text Build-type: Simple Cabal-version: >=1.6 Source-Repository head type: git location: git://github.com/ivan-m/wl-pprint-text.git Library Exposed-modules: Text.PrettyPrint.Leijen.Text, Text.PrettyPrint.Leijen.Text.Monadic Build-depends: base < 5, text >= 0.11.0.0 && < 1.3.0.0 wl-pprint-text-1.1.0.4/Text/0000755000000000000000000000000012510475415013707 5ustar0000000000000000wl-pprint-text-1.1.0.4/Text/PrettyPrint/0000755000000000000000000000000012510475415016213 5ustar0000000000000000wl-pprint-text-1.1.0.4/Text/PrettyPrint/Leijen/0000755000000000000000000000000012510475415017421 5ustar0000000000000000wl-pprint-text-1.1.0.4/Text/PrettyPrint/Leijen/Text.hs0000644000000000000000000010433212510475415020704 0ustar0000000000000000{-# LANGUAGE CPP #-} ----------------------------------------------------------------------------- -- | -- Module : Text.PrettyPrint.Leijen.Text -- Copyright : Ivan Lazar Miljenovic (c) 2010, -- Daan Leijen (c) 2000, http://www.cs.uu.nl/~daan -- License : BSD-style (see the file LICENSE) -- -- Maintainer : Ivan.Miljenovic@gmail.com -- Stability : provisional -- Portability : portable -- -- This library is a port of the /wl-pprint/ package to use 'Text' values rather than 'String's. -- -- Pretty print module based on Philip Wadler's \"prettier printer\" -- -- @ -- \"A prettier printer\" -- Draft paper, April 1997, revised March 1998. -- -- @ -- -- PPrint 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 above combinator is called '<$>'. The operator '' is used -- for soft line breaks. -- -- * There are three new primitives: 'align', 'fill' and -- 'fillBreak'. These are very useful in practice. -- -- * Lots of other useful combinators, like 'fillSep' and 'list'. -- -- * There are two renderers, 'renderPretty' for pretty printing and -- 'renderCompact' for compact output. The pretty printing algorithm -- also uses a ribbon-width now for even prettier output. -- -- * There are two displayers, 'displayT' for 'Text' values and 'displayIO' -- for file based output. -- -- * There is a 'Pretty' class. -- -- * The implementation uses optimised representations and strictness -- annotations. -- -- Ways that this library differs from /wl-pprint/ (apart from using -- 'Text' rather than 'String'): -- -- * Smarter treatment of 'empty' sub-documents (partially copied over -- from the /pretty/ library). ----------------------------------------------------------- module Text.PrettyPrint.Leijen.Text ( -- * Documents Doc, -- * Basic combinators empty, char, text, (<>), nest, line, linebreak, group, softline, softbreak, spacebreak, -- * Alignment -- -- | The combinators in this section can not be described by Wadler's -- original combinators. They align their output relative to the -- current output position - in contrast to @nest@ which always -- aligns to the current nesting level. This deprives these -- combinators from being \`optimal\'. In practice however they -- prove to be very useful. The combinators in this section should -- be used with care, since they are more expensive than the other -- combinators. For example, @align@ shouldn't be used to pretty -- print all top-level declarations of a language, but using @hang@ -- for let expressions is fine. align, hang, indent, encloseSep, list, tupled, semiBraces, -- * Operators (<+>), (<++>), (<$>), (), (<$$>), (), -- * List combinators hsep, vsep, fillSep, sep, hcat, vcat, fillCat, cat, punctuate, -- * Fillers fill, fillBreak, -- * Bracketing combinators enclose, squotes, dquotes, parens, angles, braces, brackets, -- * Character documents lparen, rparen, langle, rangle, lbrace, rbrace, lbracket, rbracket, squote, dquote, semi, colon, comma, space, dot, backslash, equals, -- * Primitive type documents string, int, integer, float, double, rational, bool, -- * Position-based combinators column, nesting, width, -- * Pretty class Pretty(..), -- * Rendering SimpleDoc(..), renderPretty, renderCompact, renderOneLine, displayB, displayT, displayIO, putDoc, hPutDoc ) where #if defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ >= 710 import Prelude hiding ((<$>)) #endif import Data.String (IsString (..)) import System.IO (Handle, hPutChar, stdout) import Data.Int (Int64) import Data.Monoid (Monoid (..)) import Data.Text.Lazy (Text) import qualified Data.Text.Lazy as T import Data.Text.Lazy.Builder (Builder) import qualified Data.Text.Lazy.Builder as B import qualified Data.Text.Lazy.IO as T infixr 5 ,,<$>,<$$> 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 :: [Doc] -> Doc 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 :: [Doc] -> Doc tupled = encloseSep lparen rparen comma -- | 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 :: [Doc] -> Doc 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 laid out with a page width of 20 as: -- -- @ -- list [10,200,3000] -- @ -- -- But when the page width is 15, it is laid out as: -- -- @ -- list [10 -- ,200 -- ,3000] -- @ encloseSep :: Doc -> Doc -> Doc -> [Doc] -> Doc encloseSep left right sp ds = case ds of [] -> left <> right [d] -> left <> d <> right _ -> align (cat (zipWith (<>) (left : repeat sp) ds) <> 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 laid out on a page width of 20 as: -- -- @ -- (words,in,a,tuple) -- @ -- -- But when the page width is 15, it is laid 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 :: Doc -> [Doc] -> [Doc] punctuate _ [] = [] punctuate _ [d] = [d] punctuate p (d:ds) = (d <> p) : punctuate p ds ----------------------------------------------------------- -- high-level combinators ----------------------------------------------------------- -- | The document @(sep xs)@ concatenates all documents @xs@ either -- horizontally with @(\<+\>)@, if it fits the page, or vertically -- with @(\<$\>)@. -- -- > sep xs = group (vsep xs) sep :: [Doc] -> Doc sep = group . vsep -- | The document @(fillSep xs)@ concatenates documents @xs@ -- horizontally with @(\<+\>)@ as long as its fits the page, then -- inserts a @line@ and continues doing that for all documents in -- @xs@. -- -- > fillSep xs = foldr () empty xs fillSep :: [Doc] -> Doc fillSep = fold () -- | The document @(hsep xs)@ concatenates all documents @xs@ -- horizontally with @(\<+\>)@. hsep :: [Doc] -> Doc hsep = fold (<+>) -- | The document @(vsep xs)@ concatenates all documents @xs@ -- vertically with @(\<$\>)@. 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 laid 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 :: [Doc] -> Doc vsep = fold (<$>) -- | The document @(cat xs)@ concatenates all documents @xs@ either -- horizontally with @(\<\>)@, if it fits the page, or vertically -- with @(\<$$\>)@. -- -- > cat xs = group (vcat xs) cat :: [Doc] -> Doc cat = group . vcat -- | The document @(fillCat xs)@ concatenates documents @xs@ -- horizontally with @(\<\>)@ as long as its fits the page, then -- inserts a @linebreak@ and continues doing that for all documents -- in @xs@. -- -- > fillCat xs = foldr () empty xs fillCat :: [Doc] -> Doc fillCat = fold () -- | The document @(hcat xs)@ concatenates all documents @xs@ -- horizontally with @(\<\>)@. hcat :: [Doc] -> Doc hcat = fold (<>) -- | The document @(vcat xs)@ concatenates all documents @xs@ -- vertically with @(\<$$\>)@. If a 'group' undoes the line breaks -- inserted by @vcat@, all documents are directly concatenated. vcat :: [Doc] -> Doc vcat = fold (<$$>) fold :: (Doc -> Doc -> Doc) -> [Doc] -> Doc fold _ [] = empty fold f ds = foldr1 f ds -- | The document @(x \<\> y)@ concatenates document @x@ and document -- @y@. It is an associative operation having 'empty' as a left and -- right unit. (infixr 6) (<>) :: Doc -> Doc -> Doc x <> y = x `beside` y -- | The document @(x \<+\> y)@ concatenates document @x@ and @y@ with -- a 'space' in between. (infixr 6) (<+>) :: Doc -> Doc -> Doc Empty <+> y = y x <+> Empty = x x <+> y = x <> space <> y -- | The document @(x \<++\> y)@ concatenates document @x@ and @y@ with -- a 'spacebreak' in between. (infixr 6) (<++>) :: Doc -> Doc -> Doc Empty <++> y = y x <++> Empty = x x <++> y = x <> spacebreak <> y -- | The document @(x \<\/\> y)@ concatenates document @x@ and @y@ -- with a 'softline' in between. This effectively puts @x@ and @y@ -- either next to each other (with a @space@ in between) or -- underneath each other. (infixr 5) () :: Doc -> Doc -> Doc () = splitWithBreak False -- | The document @(x \<\/\/\> y)@ concatenates document @x@ and @y@ -- with a 'softbreak' in between. This effectively puts @x@ and @y@ -- either right next to each other or underneath each other. (infixr -- 5) () :: Doc -> Doc -> Doc () = splitWithBreak True splitWithBreak :: Bool -> Doc -> Doc -> Doc splitWithBreak _ Empty b = b splitWithBreak _ a Empty = a splitWithBreak f a b = a <> group (Line f) <> b -- | The document @(x \<$\> y)@ concatenates document @x@ and @y@ with -- a 'line' in between. (infixr 5) (<$>) :: Doc -> Doc -> Doc (<$>) = splitWithLine False -- | The document @(x \<$$\> y)@ concatenates document @x@ and @y@ -- with a 'linebreak' in between. (infixr 5) (<$$>) :: Doc -> Doc -> Doc (<$$>) = splitWithLine True splitWithLine :: Bool -> Doc -> Doc -> Doc splitWithLine _ Empty b = b splitWithLine _ a Empty = a splitWithLine f a b = a <> Line f <> b -- | The document @softline@ behaves like 'space' if the resulting -- output fits the page, otherwise it behaves like 'line'. -- -- > softline = group line softline :: Doc 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 softbreak = group linebreak -- | The document @spacebreak@ behaves like 'space' when rendered normally -- but like 'empty' when using 'renderCompact' or 'renderOneLine'. spacebreak :: Doc spacebreak = Spaces 1 -- | Document @(squotes x)@ encloses document @x@ with single quotes -- \"'\". squotes :: Doc -> Doc squotes = enclose squote squote -- | Document @(dquotes x)@ encloses document @x@ with double quotes -- '\"'. dquotes :: Doc -> Doc dquotes = enclose dquote dquote -- | Document @(braces x)@ encloses document @x@ in braces, \"{\" and -- \"}\". braces :: Doc -> Doc braces = enclose lbrace rbrace -- | Document @(parens x)@ encloses document @x@ in parenthesis, \"(\" -- and \")\". parens :: Doc -> Doc parens = enclose lparen rparen -- | Document @(angles x)@ encloses document @x@ in angles, \"\<\" and -- \"\>\". angles :: Doc -> Doc angles = enclose langle rangle -- | Document @(brackets x)@ encloses document @x@ in square brackets, -- \"[\" and \"]\". brackets :: Doc -> Doc 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 -> Doc -> Doc -> Doc enclose l r x = l <> x <> r -- | The document @lparen@ contains a left parenthesis, \"(\". lparen :: Doc lparen = char '(' -- | The document @rparen@ contains a right parenthesis, \")\". rparen :: Doc rparen = char ')' -- | The document @langle@ contains a left angle, \"\<\". langle :: Doc langle = char '<' -- | The document @rangle@ contains a right angle, \">\". rangle :: Doc rangle = char '>' -- | The document @lbrace@ contains a left brace, \"{\". lbrace :: Doc lbrace = char '{' -- | The document @rbrace@ contains a right brace, \"}\". rbrace :: Doc rbrace = char '}' -- | The document @lbracket@ contains a left square bracket, \"[\". lbracket :: Doc lbracket = char '[' -- | The document @rbracket@ contains a right square bracket, \"]\". rbracket :: Doc rbracket = char ']' -- | The document @squote@ contains a single quote, \"'\". squote :: Doc squote = char '\'' -- | The document @dquote@ contains a double quote, '\"'. dquote :: Doc dquote = char '"' -- | The document @semi@ contains a semi colon, \";\". semi :: Doc semi = char ';' -- | The document @colon@ contains a colon, \":\". colon :: Doc colon = char ':' -- | The document @comma@ contains a comma, \",\". comma :: Doc comma = char ',' -- | The document @space@ contains a single space, \" \". -- -- > x <+> y = x <> space <> y space :: Doc space = char ' ' -- | The document @dot@ contains a single dot, \".\". dot :: Doc dot = char '.' -- | The document @backslash@ contains a back slash, \"\\\". backslash :: Doc backslash = char '\\' -- | The document @equals@ contains an equal sign, \"=\". equals :: Doc equals = char '=' ----------------------------------------------------------- -- Combinators for prelude types ----------------------------------------------------------- -- string is like "text" but replaces '\n' by "line" -- | The document @(string s)@ concatenates all characters in @s@ -- using @line@ for newline characters and @char@ for all other -- characters. It is used instead of 'text' whenever the text -- contains newline characters. string :: Text -> Doc string str = case T.uncons str of Nothing -> empty Just ('\n',str') -> line <> string str' _ -> case (T.span (/='\n') str) of (xs,ys) -> text xs <> string ys -- | The document @(bool b)@ shows the literal boolean @b@ using -- 'text'. bool :: Bool -> Doc bool b = text' b -- | The document @(int i)@ shows the literal integer @i@ using -- 'text'. int :: Int -> Doc int i = text' i -- | The document @(integer i)@ shows the literal integer @i@ using -- 'text'. integer :: Integer -> Doc integer i = text' i -- | The document @(float f)@ shows the literal float @f@ using -- 'text'. float :: Float -> Doc float f = text' f -- | The document @(double d)@ shows the literal double @d@ using -- 'text'. double :: Double -> Doc double d = text' d -- | The document @(rational r)@ shows the literal rational @r@ using -- 'text'. rational :: Rational -> Doc rational r = text' r text' :: (Show a) => a -> Doc text' = text . T.pack . show ----------------------------------------------------------- -- 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 prettyList :: [a] -> Doc prettyList = list . map pretty instance Pretty a => Pretty [a] where pretty = prettyList instance Pretty Doc where pretty = id instance Pretty Text where pretty = string instance Pretty () where pretty () = text' () instance Pretty Bool where pretty b = bool b instance Pretty Char where pretty c = char c prettyList s = string $ T.pack s instance Pretty Int where pretty i = int i instance Pretty Integer where pretty i = integer i instance Pretty Float where pretty f = float f instance Pretty Double where pretty d = double d --instance Pretty Rational where -- pretty r = rational r 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 -- nest :: Int -> Doc -> Doc -- linebreak -- :: Doc -- @ fillBreak :: Int -> Doc -> Doc fillBreak f x = width x (\w -> if (w > f) then nest f linebreak else spaced (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") -- > ,("nest","Int -> Doc -> Doc") -- > ,("linebreak","Doc")] -- > -- > ptype (name,tp) -- > = fill 6 (text name) <+> text "::" <+> text tp -- > -- > test = text "let" <+> align (vcat (map ptype types)) -- -- Which is laid out as: -- -- @ -- let empty :: Doc -- nest :: Int -> Doc -> Doc -- linebreak :: Doc -- @ fill :: Int -> Doc -> Doc fill f d = width d (\w -> if (w >= f) then empty else spaced (f - w) ) width :: Doc -> (Int -> Doc) -> Doc 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 -> Doc indent _ Empty = Empty indent i d = hang i (spaced 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 -> Doc 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 $$ y = align (x <$> y) -- -- > test = text "hi" <+> (text "nice" $$ text "world") -- -- which will be laid out as: -- -- @ -- hi nice -- world -- @ align :: Doc -> Doc 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" <$> text "world") -- -- Which would return the string \"hello\\nworld\", i.e. -- -- @ -- hello -- world -- @ data Doc = Empty | Char Char -- invariant: char is not '\n' | Text !Int64 Builder -- invariant: text doesn't contain '\n' | Line !Bool -- True <=> when undone by group, do not insert a space | Cat Doc Doc | Nest !Int64 Doc | Union Doc Doc -- invariant: first lines of first doc longer than the first lines of the second doc | Column (Int64 -> Doc) | Nesting (Int64 -> Doc) | Spaces !Int64 instance IsString Doc where fromString = string . T.pack instance Monoid Doc where mempty = empty mappend = beside -- | The data type @SimpleDoc@ represents rendered documents and is -- used by the display functions. -- -- The @Int@ in @SText@ contains the length of the string. The @Int@ -- in @SLine@ contains the indentation for that line. The library -- provides two default display functions 'displayS' and -- 'displayIO'. You can provide your own display function by writing -- a function from a @SimpleDoc@ to your own output format. data SimpleDoc = SEmpty | SChar Char SimpleDoc | SText !Int64 Builder SimpleDoc | SLine !Int64 SimpleDoc -- | The empty document is, indeed, empty. Although @empty@ has no -- content, it does have a \'height\' of 1 and behaves exactly like -- @(text \"\")@ (and is therefore not a unit of @\<$\>@). empty :: Doc empty = Empty -- | 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 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 :: Text -> Doc text s | T.null s = Empty | otherwise = Text (T.length s) (B.fromLazyText 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' or if rendered with -- 'renderOneLine'. line :: Doc line = Line False -- | 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 linebreak = Line True beside :: Doc -> Doc -> Doc beside Empty r = r beside l Empty = l beside l r = Cat l r -- | 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" <$> text "world") <$> text "!" -- -- outputs as: -- -- @ -- hello -- world -- ! -- @ nest :: Int -> Doc -> Doc nest _ Empty = Empty nest i x = Nest (fromIntegral i) x -- | Specifies how to create the document based upon which column it is in. column :: (Int -> Doc) -> Doc column f = Column (f . fromIntegral) -- | Specifies how to nest the document based upon which column it is -- being nested in. nesting :: (Int -> Doc) -> Doc nesting f = Nesting (f . fromIntegral) -- | 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 -> Doc group x = Union (flatten x) x flatten :: Doc -> Doc flatten (Cat x y) = Cat (flatten x) (flatten y) flatten (Nest i x) = Nest i (flatten x) flatten (Line brk) = if brk then Empty else Text 1 (B.singleton ' ') flatten (Union x _) = flatten x flatten (Column f) = Column (flatten . f) flatten (Nesting f) = Nesting (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 = Nil | Cons !Int64 Doc Docs -- | 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 -> SimpleDoc renderPretty rfrac w doc = best 0 0 (Cons 0 doc Nil) where -- r :: the ribbon width in characters r = max 0 (min w64 (round (fromIntegral w * rfrac))) w64 = fromIntegral w -- 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 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) 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)) Union x y -> nicest n k (best n k $ Cons i x ds) (best n k $ Cons i y ds) Column f -> best n k (Cons i (f k) ds) Nesting f -> best n k (Cons i (f i) ds) Spaces l -> let k' = k+l in seq k' $ SText l (spaces l) (best n k' ds) --nicest :: r = ribbon width, w = page width, -- n = indentation of current line, k = current column -- x and y, the (simple) documents to chose from. -- precondition: first lines of x are longer than the first lines of y. nicest n k x y | fits wth x = x | otherwise = y where wth = min (w64 - k) (r - k + n) fits :: Int64 -> SimpleDoc -> Bool fits w _ | w < 0 = False fits _ SEmpty = True fits w (SChar _ x) = fits (w - 1) x fits w (SText l _ x) = fits (w - l) x fits _ SLine{} = True ----------------------------------------------------------- -- 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 -> SimpleDoc renderCompact dc = scan 0 [dc] where scan _ [] = SEmpty scan k (d:ds) = case d of 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)) Line _ -> SLine 0 (scan 0 ds) Cat x y -> scan k (x:y:ds) Nest _ x -> scan k (x:ds) Union _ y -> scan k (y:ds) Column f -> scan k (f k:ds) Nesting f -> scan k (f 0:ds) Spaces _ -> scan k ds -- | @(renderOneLine x)@ renders document @x@ without adding any -- indentation or newlines. renderOneLine :: Doc -> SimpleDoc renderOneLine dc = scan 0 [dc] where scan _ [] = SEmpty scan k (d:ds) = case d of 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)) Line False -> let k' = k+1 in seq k' (SChar ' ' (scan k' ds)) Line _ -> scan k ds Cat x y -> scan k (x:y:ds) Nest _ x -> scan k (x:ds) Union _ y -> scan k (y:ds) Column f -> scan k (f k:ds) Nesting f -> scan k (f 0:ds) Spaces _ -> scan k ds ----------------------------------------------------------- -- Displayers: displayS and displayIO ----------------------------------------------------------- -- | @(displayB simpleDoc)@ takes the output @simpleDoc@ from a -- rendering function and transforms it to a 'Builder' type (for -- further manipulation before converting to a lazy 'Text'). displayB :: SimpleDoc -> Builder displayB SEmpty = mempty displayB (SChar c x) = c `consB` displayB x displayB (SText _ s x) = s `mappend` displayB x displayB (SLine i x) = '\n' `consB` (indentation i `mappend` displayB x) consB :: Char -> Builder -> Builder c `consB` b = B.singleton c `mappend` b -- | @(displayT simpleDoc)@ takes the output @simpleDoc@ from a -- rendering function and transforms it to a lazy 'Text' value. -- -- > showWidth :: Int -> Doc -> Text -- > showWidth w x = displayT (renderPretty 0.4 w x) displayT :: SimpleDoc -> Text displayT = B.toLazyText . displayB -- | @(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 -> IO () displayIO handle simpleDoc = display simpleDoc where display SEmpty = return () display (SChar c x) = hPutChar handle c >> display x display (SText _ s x) = T.hPutStr handle (B.toLazyText s) >> display x display (SLine i x) = T.hPutStr handle newLine >> display x where newLine = B.toLazyText $ '\n' `consB` indentation i ----------------------------------------------------------- -- default pretty printers: show, putDoc and hPutDoc ----------------------------------------------------------- instance Show Doc where showsPrec d doc = showsPrec d (displayT $ renderPretty 0.4 80 doc) show doc = T.unpack (displayT $ renderPretty 0.4 80 doc) instance Show SimpleDoc where show simpleDoc = T.unpack (displayT simpleDoc) -- | 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 -> 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' -- > ['T.pack' "vertical", 'T.pack' "text"])) -- > 'hClose' handle hPutDoc :: Handle -> Doc -> 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 :: Int64 -> Builder spaces n | n <= 0 = mempty | otherwise = B.fromLazyText $ T.replicate n (T.singleton ' ') spaced :: Int -> Doc spaced l = Spaces l' where l' = fromIntegral l -- An alias for readability purposes indentation :: Int64 -> Builder indentation = spaces -- LocalWords: PPrint combinators Wadler Wadler's encloseSep wl-pprint-text-1.1.0.4/Text/PrettyPrint/Leijen/Text/0000755000000000000000000000000012510475415020345 5ustar0000000000000000wl-pprint-text-1.1.0.4/Text/PrettyPrint/Leijen/Text/Monadic.hs0000644000000000000000000005015412510475415022260 0ustar0000000000000000{-# LANGUAGE CPP, FlexibleInstances #-} ----------------------------------------------------------------------------- -- | -- Module : Text.PrettyPrint.Leijen.Text.Monadic -- Copyright : Ivan Lazar Miljenovic (c) 2010, -- Daan Leijen (c) 2000, http://www.cs.uu.nl/~daan -- License : BSD-style (see the file LICENSE) -- -- Maintainer : Ivan.Miljenovic@gmail.com -- Stability : provisional -- Portability : portable -- -- This module provides a version of -- "Text.PrettyPrint.Leijen.Text" where the combinators have been -- lifted into a 'Monad'. The main usage for this is for state-based -- pretty-printing. ----------------------------------------------------------- module Text.PrettyPrint.Leijen.Text.Monadic ( -- * Documents Doc, -- putDoc, hPutDoc, -- * Basic combinators empty, char, text, (<>), nest, line, linebreak, group, softline, softbreak, spacebreak, -- * 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 (<+>), (<++>), (<$>), (), (<$$>), (), -- * List combinators hsep, vsep, fillSep, sep, hcat, vcat, fillCat, cat, punctuate, -- * Fillers fill, fillBreak, -- * Bracketing combinators enclose, squotes, dquotes, parens, angles, braces, brackets, -- * Character documents lparen, rparen, langle, rangle, lbrace, rbrace, lbracket, rbracket, squote, dquote, semi, colon, comma, space, dot, backslash, equals, -- * Primitive type documents string, int, integer, float, double, rational, bool, -- * Position-based combinators column, nesting, width, -- * Pretty class Pretty(..), prettyM, -- * Rendering SimpleDoc(..), renderPretty, renderCompact, renderOneLine, displayB, displayT, displayIO, putDoc, hPutDoc ) where #if defined(__GLASGOW_HASKELL__) && __GLASGOW_HASKELL__ >= 710 import Prelude hiding ((<$>)) #endif import Text.PrettyPrint.Leijen.Text (Doc, Pretty (..), SimpleDoc (..), displayB, displayIO, displayT, hPutDoc, putDoc, renderCompact, renderOneLine, renderPretty) import qualified Text.PrettyPrint.Leijen.Text as PP import Control.Monad (liftM, liftM2, liftM3, liftM4) import Data.String (IsString (..)) import Data.Text.Lazy (Text) infixr 5 ,,<$>,<$$> infixr 6 <>,<+>,<++> instance Monad m => IsString (m Doc) where fromString = string . fromString ----------------------------------------------------------- -- | 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 :: (Monad m) => m [Doc] -> m Doc list = liftM PP.list -- | 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 :: (Monad m) => m [Doc] -> m Doc tupled = liftM PP.tupled -- | 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 :: (Monad m) => m [Doc] -> m Doc semiBraces = liftM PP.semiBraces -- | 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 laid out with a page width of 20 as: -- -- @ -- list [10,200,3000] -- @ -- -- But when the page width is 15, it is laid out as: -- -- @ -- list [10 -- ,200 -- ,3000] -- @ encloseSep :: (Monad m) => m Doc -> m Doc -> m Doc -> m [Doc] -> m Doc encloseSep = liftM4 PP.encloseSep -- | @(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 laid out on a page width of 20 as: -- -- @ -- (words,in,a,tuple) -- @ -- -- But when the page width is 15, it is laid 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 :: (Monad m) => m Doc -> m [Doc] -> m [Doc] punctuate = liftM2 PP.punctuate -- | The document @(sep xs)@ concatenates all documents @xs@ either -- horizontally with @(\<+\>)@, if it fits the page, or vertically -- with @(\<$\>)@. -- -- > sep xs = group (vsep xs) sep :: (Monad m) => m [Doc] -> m Doc sep = liftM PP.sep -- | The document @(fillSep xs)@ concatenates documents @xs@ -- horizontally with @(\<+\>)@ as long as its fits the page, then -- inserts a @line@ and continues doing that for all documents in -- @xs@. -- -- > fillSep xs = foldr () empty xs fillSep :: (Monad m) => m [Doc] -> m Doc fillSep = liftM PP.fillSep -- | The document @(hsep xs)@ concatenates all documents @xs@ -- horizontally with @(\<+\>)@. hsep :: (Monad m) => m [Doc] -> m Doc hsep = liftM PP.hsep -- | The document @(vsep xs)@ concatenates all documents @xs@ -- vertically with @(\<$\>)@. 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 laid 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 :: (Monad m) => m [Doc] -> m Doc vsep = liftM PP.vsep -- | The document @(cat xs)@ concatenates all documents @xs@ either -- horizontally with @(\<\>)@, if it fits the page, or vertically -- with @(\<$$\>)@. -- -- > cat xs = group (vcat xs) cat :: (Monad m) => m [Doc] -> m Doc cat = liftM PP.cat -- | The document @(fillCat xs)@ concatenates documents @xs@ -- horizontally with @(\<\>)@ as long as its fits the page, then -- inserts a @linebreak@ and continues doing that for all documents -- in @xs@. -- -- > fillCat xs = foldr () empty xs fillCat :: (Monad m) => m [Doc] -> m Doc fillCat = liftM PP.fillCat -- | The document @(hcat xs)@ concatenates all documents @xs@ -- horizontally with @(\<\>)@. hcat :: (Monad m) => m [Doc] -> m Doc hcat = liftM PP.hcat -- | The document @(vcat xs)@ concatenates all documents @xs@ -- vertically with @(\<$$\>)@. If a 'group' undoes the line breaks -- inserted by @vcat@, all documents are directly concatenated. vcat :: (Monad m) => m [Doc] -> m Doc vcat = liftM PP.vcat -- | The document @(x \<\> y)@ concatenates document @x@ and document -- @y@. It is an associative operation having 'empty' as a left and -- right unit. (infixr 6) (<>) :: (Monad m) => m Doc -> m Doc -> m Doc (<>) = liftM2 (PP.<>) -- | The document @(x \<+\> y)@ concatenates document @x@ and @y@ with -- a 'space' in between. (infixr 6) (<+>) :: (Monad m) => m Doc -> m Doc -> m Doc (<+>) = liftM2 (PP.<+>) -- | The document @(x \<++\> y)@ concatenates document @x@ and @y@ with -- a 'spacebreak' in between. (infixr 6) (<++>) :: (Monad m) => m Doc -> m Doc -> m Doc (<++>) = liftM2 (PP.<++>) -- | 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) () :: (Monad m) => m Doc -> m Doc -> m Doc () = liftM2 (PP.) -- | 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) () :: (Monad m) => m Doc -> m Doc -> m Doc () = liftM2 (PP.) -- | The document @(x \<$\> y)@ concatenates document @x@ and @y@ with -- a 'line' in between. (infixr 5) (<$>) :: (Monad m) => m Doc -> m Doc -> m Doc (<$>) = liftM2 (PP.<$>) -- | The document @(x \<$$\> y)@ concatenates document @x@ and @y@ -- with a 'linebreak' in between. (infixr 5) (<$$>) :: (Monad m) => m Doc -> m Doc -> m Doc (<$$>) = liftM2 (PP.<$$>) -- | The document @softline@ behaves like 'space' if the resulting -- output fits the page, otherwise it behaves like 'line'. softline :: (Monad m) => m Doc softline = return PP.softline -- | The document @softbreak@ behaves like 'empty' if the resulting -- output fits the page, otherwise it behaves like 'line'. softbreak :: (Monad m) => m Doc softbreak = return PP.softbreak -- | The document @spacebreak@ behaves like 'space' when rendered normally -- but like 'empty' when using 'renderCompact' or 'renderOneLine'. spacebreak :: (Monad m) => m Doc spacebreak = return PP.spacebreak -- | Document @(squotes x)@ encloses document @x@ with single quotes -- \"'\". squotes :: (Monad m) => m Doc -> m Doc squotes = liftM PP.squotes -- | Document @(dquotes x)@ encloses document @x@ with double quotes -- '\"'. dquotes :: (Monad m) => m Doc -> m Doc dquotes = liftM PP.dquotes -- | Document @(braces x)@ encloses document @x@ in braces, \"{\" and -- \"}\". braces :: (Monad m) => m Doc -> m Doc braces = liftM PP.braces -- | Document @(parens x)@ encloses document @x@ in parenthesis, \"(\" -- and \")\". parens :: (Monad m) => m Doc -> m Doc parens = liftM PP.parens -- | Document @(angles x)@ encloses document @x@ in angles, \"\<\" and -- \"\>\". angles :: (Monad m) => m Doc -> m Doc angles = liftM PP.angles -- | Document @(brackets x)@ encloses document @x@ in square brackets, -- \"[\" and \"]\". brackets :: (Monad m) => m Doc -> m Doc brackets = liftM PP.brackets -- | The document @(enclose l r x)@ encloses document @x@ between -- documents @l@ and @r@ using @(\<\>)@. -- -- > enclose l r x = l <> x <> r enclose :: (Monad m) => m Doc -> m Doc -> m Doc -> m Doc enclose = liftM3 PP.enclose -- | The document @lparen@ contains a left parenthesis, \"(\". lparen :: (Monad m) => m Doc lparen = return PP.lparen -- | The document @rparen@ contains a right parenthesis, \")\". rparen :: (Monad m) => m Doc rparen = return PP.rparen -- | The document @langle@ contains a left angle, \"\<\". langle :: (Monad m) => m Doc langle = return PP.langle -- | The document @rangle@ contains a right angle, \">\". rangle :: (Monad m) => m Doc rangle = return PP.rangle -- | The document @lbrace@ contains a left brace, \"{\". lbrace :: (Monad m) => m Doc lbrace = return PP.lbrace -- | The document @rbrace@ contains a right brace, \"}\". rbrace :: (Monad m) => m Doc rbrace = return PP.rbrace -- | The document @lbracket@ contains a left square bracket, \"[\". lbracket :: (Monad m) => m Doc lbracket = return PP.lbracket -- | The document @rbracket@ contains a right square bracket, \"]\". rbracket :: (Monad m) => m Doc rbracket = return PP.rbracket -- | The document @squote@ contains a single quote, \"'\". squote :: (Monad m) => m Doc squote = return PP.squote -- | The document @dquote@ contains a double quote, '\"'. dquote :: (Monad m) => m Doc dquote = return PP.dquote -- | The document @semi@ contains a semi colon, \";\". semi :: (Monad m) => m Doc semi = return PP.semi -- | The document @colon@ contains a colon, \":\". colon :: (Monad m) => m Doc colon = return PP.colon -- | The document @comma@ contains a comma, \",\". comma :: (Monad m) => m Doc comma = return PP.comma -- | The document @space@ contains a single space, \" \". -- -- > x <+> y = x <> space <> y space :: (Monad m) => m Doc space = return PP.space -- | The document @dot@ contains a single dot, \".\". dot :: (Monad m) => m Doc dot = return PP.dot -- | The document @backslash@ contains a back slash, \"\\\". backslash :: (Monad m) => m Doc backslash = return PP.backslash -- | The document @equals@ contains an equal sign, \"=\". equals :: (Monad m) => m Doc equals = return PP.equals ----------------------------------------------------------- -- Combinators for prelude types ----------------------------------------------------------- -- | The document @(string s)@ concatenates all characters in @s@ -- using @line@ for newline characters and @char@ for all other -- characters. It is used instead of 'text' whenever the text -- contains newline characters. string :: (Monad m) => Text -> m Doc string = return . PP.string -- | The document @(bool b)@ shows the literal boolean @b@ using -- 'text'. bool :: (Monad m) => Bool -> m Doc bool = return . PP.bool -- | The document @(int i)@ shows the literal integer @i@ using -- 'text'. int :: (Monad m) => Int -> m Doc int = return . PP.int -- | The document @(integer i)@ shows the literal integer @i@ using -- 'text'. integer :: (Monad m) => Integer -> m Doc integer = return . PP.integer -- | The document @(float f)@ shows the literal float @f@ using -- 'text'. float :: (Monad m) => Float -> m Doc float = return . PP.float -- | The document @(double d)@ shows the literal double @d@ using -- 'text'. double :: (Monad m) => Double -> m Doc double = return . PP.double -- | The document @(rational r)@ shows the literal rational @r@ using -- 'text'. rational :: (Monad m) => Rational -> m Doc rational = return . PP.rational -- | A monadic version of 'pretty'; this is to allow you to use the -- 'Pretty' class without having to create extra instances. -- Alternatively, you may wish to make a variant of 'Pretty' using -- the actual 'Monad' to be used. prettyM :: (Pretty a, Monad m) => a -> m Doc prettyM = return . pretty -- | 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") -- > ,("nest","Int -> Doc -> Doc") -- > ,("linebreak","Doc")] -- > -- > ptype (name,tp) -- > = fill 6 (text name) <+> text "::" <+> text tp -- > -- > test = text "let" <+> align (vcat (map ptype types)) -- -- Which is laid out as: -- -- @ -- let empty :: Doc -- nest :: Int -> Doc -> Doc -- linebreak :: Doc -- @ fill :: (Monad m) => Int -> m Doc -> m Doc fill = liftM . PP.fill width :: (Monad m) => m Doc -> m (Int -> Doc) -> m Doc width = liftM2 PP.width -- | 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 -- nest :: Int -> Doc -> Doc -- linebreak -- :: Doc -- @ fillBreak :: (Monad m) => Int -> m Doc -> m Doc fillBreak = liftM . PP.fillBreak -- | 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 :: (Monad m) => Int -> m Doc -> m Doc indent = liftM . PP.indent -- | 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 :: (Monad m) => Int -> m Doc -> m Doc hang = liftM . PP.hang -- | 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 $$ y = align (x <$> y) -- -- > test = text "hi" <+> (text "nice" $$ text "world") -- -- which will be laid out as: -- -- @ -- hi nice -- world -- @ align :: (Monad m) => m Doc -> m Doc align = liftM PP.align -- | 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 @\<$\>@). empty :: (Monad m) => m Doc empty = return PP.empty -- | The document @(char c)@ contains the literal character @c@. The -- character shouldn't be a newline (@'\n'@), the function 'line' -- should be used for line breaks. char :: (Monad m) => Char -> m Doc char = return . PP.char -- | The document @(text s)@ contains the literal string @s@. The -- string shouldn't contain any newline (@'\n'@) characters. If the -- string contains newline characters, the function 'string' should -- be used. text :: (Monad m) => Text -> m Doc text = return . PP.text -- | The @line@ document advances to the next line and indents to the -- current nesting level. Document @line@ behaves like @(text \" -- \")@ if the line break is undone by 'group' or if rendered with -- 'renderOneLine'. line :: (Monad m) => m Doc line = return PP.line -- | The @linebreak@ document advances to the next line and indents to -- the current nesting level. Document @linebreak@ behaves like -- 'empty' if the line break is undone by 'group'. linebreak :: (Monad m) => m Doc linebreak = return PP.linebreak -- | The document @(nest i x)@ renders document @x@ with the current -- indentation level increased by @i@ (See also 'hang', 'align' and -- 'indent'). -- -- > nest 2 (text "hello" <$> text "world") <$> text "!" -- -- outputs as: -- -- @ -- hello -- world -- ! -- @ nest :: (Monad m) => Int -> m Doc -> m Doc nest = liftM . PP.nest -- | Specifies how to create the document based upon which column it is in. column :: (Monad m) => m (Int -> Doc) -> m Doc column = liftM PP.column -- | Specifies how to nest the document based upon which column it is -- being nested in. nesting :: (Monad m) => m (Int -> Doc) -> m Doc nesting = liftM PP.nesting -- | 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 :: (Monad m) => m Doc -> m Doc group = liftM PP.group