pretty-1.1.3.6: Pretty-printing library

Copyright(c) The University of Glasgow 2001
LicenseBSD-style (see the file LICENSE)
MaintainerDavid Terei <code@davidterei.com>
Stabilitystable
Portabilityportable
Safe HaskellSafe
LanguageHaskell98

Text.PrettyPrint

Contents

Description

Provides a collection of pretty printer combinators, a set of API's that provides a way to easily print out text in a consistent format of your choosing.

This module should be used as opposed to the HughesPJ module. Both are equivalent though as this module simply re-exports the other.

Synopsis

The document type

data Doc Source #

The abstract type of documents. A Doc represents a set of layouts. A Doc with no occurrences of Union or NoDoc represents just one layout.

Instances

Eq Doc Source # 

Methods

(==) :: Doc -> Doc -> Bool #

(/=) :: Doc -> Doc -> Bool #

Show Doc Source # 

Methods

showsPrec :: Int -> Doc -> ShowS #

show :: Doc -> String #

showList :: [Doc] -> ShowS #

IsString Doc Source # 

Methods

fromString :: String -> Doc #

Generic Doc Source # 

Associated Types

type Rep Doc :: * -> * #

Methods

from :: Doc -> Rep Doc x #

to :: Rep Doc x -> Doc #

Semigroup Doc Source # 

Methods

(<>) :: Doc -> Doc -> Doc #

sconcat :: NonEmpty Doc -> Doc #

stimes :: Integral b => b -> Doc -> Doc #

Monoid Doc Source # 

Methods

mempty :: Doc #

mappend :: Doc -> Doc -> Doc #

mconcat :: [Doc] -> Doc #

NFData Doc Source # 

Methods

rnf :: Doc -> () #

type Rep Doc Source # 
type Rep Doc = D1 * (MetaData "Doc" "Text.PrettyPrint.HughesPJ" "pretty-1.1.3.6-DEgb37EtwBsKE2k5WIQDrp" True) (C1 * (MetaCons "Doc" PrefixI False) (S1 * (MetaSel (Nothing Symbol) NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 * (Doc ()))))

Constructing documents

Converting values into documents

char :: Char -> Doc Source #

A document of height and width 1, containing a literal character.

text :: String -> Doc Source #

A document of height 1 containing a literal string. text satisfies the following laws:

The side condition on the last law is necessary because text "" has height 1, while empty has no height.

ptext :: String -> Doc Source #

Same as text. Used to be used for Bytestrings.

sizedText :: Int -> String -> Doc Source #

Some text with any width. (text s = sizedText (length s) s)

zeroWidthText :: String -> Doc Source #

Some text, but without any width. Use for non-printing text such as a HTML or Latex tags

int Source #

Arguments

:: Int 
-> Doc
int n = text (show n)

integer Source #

Arguments

:: Integer 
-> Doc
integer n = text (show n)

float Source #

Arguments

:: Float 
-> Doc
float n = text (show n)

double Source #

Arguments

:: Double 
-> Doc
double n = text (show n)

rational Source #

Arguments

:: Rational 
-> Doc
rational n = text (show n)

Simple derived documents

semi Source #

Arguments

:: Doc

A ';' character

comma Source #

Arguments

:: Doc

A ',' character

colon Source #

Arguments

:: Doc

A : character

space Source #

Arguments

:: Doc

A space character

equals Source #

Arguments

:: Doc

A '=' character

lparen Source #

Arguments

:: Doc

A '(' character

rparen Source #

Arguments

:: Doc

A ')' character

lbrack Source #

Arguments

:: Doc

A '[' character

rbrack Source #

Arguments

:: Doc

A ']' character

lbrace Source #

Arguments

:: Doc

A '{' character

rbrace Source #

Arguments

:: Doc

A '}' character

Wrapping documents in delimiters

parens Source #

Arguments

:: Doc 
-> Doc

Wrap document in (...)

brackets Source #

Arguments

:: Doc 
-> Doc

Wrap document in [...]

braces Source #

Arguments

:: Doc 
-> Doc

Wrap document in {...}

quotes Source #

Arguments

:: Doc 
-> Doc

Wrap document in '...'

doubleQuotes Source #

Arguments

:: Doc 
-> Doc

Wrap document in "..."

Combining documents

empty :: Doc Source #

The empty document, with no height and no width. empty is the identity for <>, <+>, $$ and $+$, and anywhere in the argument list for sep, hcat, hsep, vcat, fcat etc.

(<>) :: Doc -> Doc -> Doc infixl 6 Source #

Beside. <> is associative, with identity empty.

(<+>) :: Doc -> Doc -> Doc infixl 6 Source #

Beside, separated by space, unless one of the arguments is empty. <+> is associative, with identity empty.

hcat :: [Doc] -> Doc Source #

List version of <>.

hsep :: [Doc] -> Doc Source #

List version of <+>.

($$) :: Doc -> Doc -> Doc infixl 5 Source #

Above, except that if the last line of the first argument stops at least one position before the first line of the second begins, these two lines are overlapped. For example:

   text "hi" $$ nest 5 (text "there")

lays out as

   hi   there

rather than

   hi
        there

$$ is associative, with identity empty, and also satisfies

  • (x $$ y) <> z = x $$ (y <> z), if y non-empty.

($+$) :: Doc -> Doc -> Doc infixl 5 Source #

Above, with no overlapping. $+$ is associative, with identity empty.

vcat :: [Doc] -> Doc Source #

List version of $$.

sep :: [Doc] -> Doc Source #

Either hsep or vcat.

cat :: [Doc] -> Doc Source #

Either hcat or vcat.

fsep :: [Doc] -> Doc Source #

"Paragraph fill" version of sep.

fcat :: [Doc] -> Doc Source #

"Paragraph fill" version of cat.

nest :: Int -> Doc -> Doc Source #

Nest (or indent) a document by a given number of positions (which may also be negative). nest satisfies the laws:

The side condition on the last law is needed because empty is a left identity for <>.

hang :: Doc -> Int -> Doc -> Doc Source #

hang d1 n d2 = sep [d1, nest n d2]

punctuate :: Doc -> [Doc] -> [Doc] Source #

punctuate p [d1, ... dn] = [d1 <> p, d2 <> p, ... dn-1 <> p, dn]

Predicates on documents

isEmpty :: Doc -> Bool Source #

Returns True if the document is empty

Rendering documents

Default rendering

render :: Doc -> String Source #

Render the Doc to a String using the default Style (see style).

Rendering with a particular style

data Style Source #

A rendering style. Allows us to specify constraints to choose among the many different rendering options.

Constructors

Style 

Fields

  • mode :: Mode

    The rendering mode.

  • lineLength :: Int

    Maximum length of a line, in characters.

  • ribbonsPerLine :: Float

    Ratio of line length to ribbon length. A ribbon refers to the characters on a line excluding indentation. So a lineLength of 100, with a ribbonsPerLine of 2.0 would only allow up to 50 characters of ribbon to be displayed on a line, while allowing it to be indented up to 50 characters.

Instances

Eq Style Source # 

Methods

(==) :: Style -> Style -> Bool #

(/=) :: Style -> Style -> Bool #

Show Style Source # 

Methods

showsPrec :: Int -> Style -> ShowS #

show :: Style -> String #

showList :: [Style] -> ShowS #

Generic Style Source # 

Associated Types

type Rep Style :: * -> * #

Methods

from :: Style -> Rep Style x #

to :: Rep Style x -> Style #

type Rep Style Source # 
type Rep Style = D1 * (MetaData "Style" "Text.PrettyPrint.Annotated.HughesPJ" "pretty-1.1.3.6-DEgb37EtwBsKE2k5WIQDrp" False) (C1 * (MetaCons "Style" PrefixI True) ((:*:) * (S1 * (MetaSel (Just Symbol "mode") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 * Mode)) ((:*:) * (S1 * (MetaSel (Just Symbol "lineLength") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 * Int)) (S1 * (MetaSel (Just Symbol "ribbonsPerLine") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 * Float)))))

style :: Style Source #

The default style (mode=PageMode, lineLength=100, ribbonsPerLine=1.5).

renderStyle :: Style -> Doc -> String Source #

Render the Doc to a String using the given Style.

General rendering

fullRender Source #

Arguments

:: Mode

Rendering mode.

-> Int

Line length.

-> Float

Ribbons per line.

-> (TextDetails -> a -> a)

What to do with text.

-> a

What to do at the end.

-> Doc

The document.

-> a

Result.

The general rendering interface. Please refer to the Style and Mode types for a description of rendering mode, line length and ribbons.

data Mode Source #

Rendering mode.

Constructors

PageMode

Normal rendering (lineLength and ribbonsPerLine respected').

ZigZagMode

With zig-zag cuts.

LeftMode

No indentation, infinitely long lines (lineLength ignored), but explicit new lines, i.e., text "one" $$ text "two", are respected.

OneLineMode

All on one line, lineLength ignored and explicit new lines ($$) are turned into spaces.

Instances

Eq Mode Source # 

Methods

(==) :: Mode -> Mode -> Bool #

(/=) :: Mode -> Mode -> Bool #

Show Mode Source # 

Methods

showsPrec :: Int -> Mode -> ShowS #

show :: Mode -> String #

showList :: [Mode] -> ShowS #

Generic Mode Source # 

Associated Types

type Rep Mode :: * -> * #

Methods

from :: Mode -> Rep Mode x #

to :: Rep Mode x -> Mode #

type Rep Mode Source # 
type Rep Mode = D1 * (MetaData "Mode" "Text.PrettyPrint.Annotated.HughesPJ" "pretty-1.1.3.6-DEgb37EtwBsKE2k5WIQDrp" False) ((:+:) * ((:+:) * (C1 * (MetaCons "PageMode" PrefixI False) (U1 *)) (C1 * (MetaCons "ZigZagMode" PrefixI False) (U1 *))) ((:+:) * (C1 * (MetaCons "LeftMode" PrefixI False) (U1 *)) (C1 * (MetaCons "OneLineMode" PrefixI False) (U1 *))))

data TextDetails Source #

A TextDetails represents a fragment of text that will be output at some point in a Doc.

Constructors

Chr !Char

A single Char fragment

Str String

A whole String fragment

PStr String

Used to represent a Fast String fragment but now deprecated and identical to the Str constructor.