TPDB.Pretty

Documentation

data Doc ann

The abstract data type Doc ann represents pretty documents that have been annotated with data of type ann.

More specifically, a value of type Doc represents a non-empty set of possible layouts of a document. The layout functions select one of these possibilities, taking into account things like the width of the output document.

The annotation is an arbitrary piece of data associated with (part of) a document. Annotations may be used by the rendering backends in order to display output differently, such as

• color information (e.g. when rendering to the terminal)
• mouseover text (e.g. when rendering to rich HTML)
• whether to show something or not (to allow simple or detailed versions)

The simplest way to display a Doc is via the Show class.

>>> putStrLn (show (vsep ["hello", "world"]))
hello
world

Instances

Functor Doc

Alter the document’s annotations.

This instance makes Doc more flexible (because it can be used in Functor-polymorphic values), but fmap is much less readable compared to using reAnnotate in code that only works for Doc anyway. Consider using the latter when the type does not matter.

Defined in Prettyprinter.Internal

Methods

fmap :: (a -> b) -> Doc a -> Doc b

(<$) :: a -> Doc b -> Doc a

Show (Doc ann)

(show doc) prettyprints document doc with defaultLayoutOptions, ignoring all annotations.

Defined in Prettyprinter.Internal

Methods

showsPrec :: Int -> Doc ann -> ShowS

show :: Doc ann -> String

showList :: [Doc ann] -> ShowS

IsString (Doc ann)

>>> pretty ("hello\nworld")
hello
world

This instance uses the Pretty Text instance, and uses the same newline to line conversion.

Defined in Prettyprinter.Internal

Methods

fromString :: String -> Doc ann

Generic (Doc ann)

Defined in Prettyprinter.Internal

Associated Types

type Rep (Doc ann) :: Type -> Type

Methods

from :: Doc ann -> Rep (Doc ann) x

to :: Rep (Doc ann) x -> Doc ann

Semigroup (Doc ann)

x <> y = hcat [x, y]

>>> "hello" <> "world" :: Doc ann
helloworld

Defined in Prettyprinter.Internal

Methods

(<>) :: Doc ann -> Doc ann -> Doc ann

sconcat :: NonEmpty (Doc ann) -> Doc ann

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

Monoid (Doc ann)

mempty = emptyDoc
mconcat = hcat

>>> mappend "hello" "world" :: Doc ann
helloworld

Defined in Prettyprinter.Internal

Methods

mempty :: Doc ann

mappend :: Doc ann -> Doc ann -> Doc ann

mconcat :: [Doc ann] -> Doc ann

type Rep (Doc ann)

Defined in Prettyprinter.Internal

type Rep (Doc ann) = D1 ('MetaData "Doc" "Prettyprinter.Internal" "prettyprinter-1.7.1-BauxLiNvN3EiJKyXe93SM" 'False) (((C1 ('MetaCons "Fail" 'PrefixI 'False) (U1 :: Type -> Type) :+: (C1 ('MetaCons "Empty" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "Char" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Char)))) :+: (C1 ('MetaCons "Text" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Int) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Text)) :+: (C1 ('MetaCons "Line" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "FlatAlt" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Doc ann)) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Doc ann)))))) :+: ((C1 ('MetaCons "Cat" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Doc ann)) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Doc ann))) :+: (C1 ('MetaCons "Nest" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Int) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Doc ann))) :+: C1 ('MetaCons "Union" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Doc ann)) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Doc ann))))) :+: ((C1 ('MetaCons "Column" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Int -> Doc ann))) :+: C1 ('MetaCons "WithPageWidth" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (PageWidth -> Doc ann)))) :+: (C1 ('MetaCons "Nesting" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Int -> Doc ann))) :+: C1 ('MetaCons "Annotated" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 ann) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Doc ann)))))))

class Pretty a where

Overloaded conversion to Doc.

Laws:

1. output should be pretty. :-)

Minimal complete definition

pretty

Methods

pretty :: a -> Doc ann

>>> pretty 1 <+> pretty "hello" <+> pretty 1.234
1 hello 1.234

prettyList :: [a] -> Doc ann

prettyList is only used to define the instance Pretty a => Pretty [a]. In normal circumstances only the pretty function is used.

>>> prettyList [1, 23, 456]
[1, 23, 456]

Instances

Pretty Bool

>>> pretty True
True

Defined in Prettyprinter.Internal

Methods

pretty :: Bool -> Doc ann

prettyList :: [Bool] -> Doc ann

Pretty Char

Instead of (pretty 'n'), consider using line as a more readable alternative.

>>> pretty 'f' <> pretty 'o' <> pretty 'o'
foo
>>> pretty ("string" :: String)
string

Defined in Prettyprinter.Internal

Methods

pretty :: Char -> Doc ann

prettyList :: [Char] -> Doc ann

Pretty Double

>>> pretty (exp 1 :: Double)
2.71828182845904...

Defined in Prettyprinter.Internal

Methods

pretty :: Double -> Doc ann

prettyList :: [Double] -> Doc ann

Pretty Float

>>> pretty (pi :: Float)
3.1415927

Defined in Prettyprinter.Internal

Methods

pretty :: Float -> Doc ann

prettyList :: [Float] -> Doc ann

Pretty Int

>>> pretty (123 :: Int)
123

Defined in Prettyprinter.Internal

Methods

pretty :: Int -> Doc ann

prettyList :: [Int] -> Doc ann

Pretty Int8

Defined in Prettyprinter.Internal

Methods

pretty :: Int8 -> Doc ann

prettyList :: [Int8] -> Doc ann

Pretty Int16

Defined in Prettyprinter.Internal

Methods

pretty :: Int16 -> Doc ann

prettyList :: [Int16] -> Doc ann

Pretty Int32

Defined in Prettyprinter.Internal

Methods

pretty :: Int32 -> Doc ann

prettyList :: [Int32] -> Doc ann

Pretty Int64

Defined in Prettyprinter.Internal

Methods

pretty :: Int64 -> Doc ann

prettyList :: [Int64] -> Doc ann

Pretty Integer

>>> pretty (2^123 :: Integer)
10633823966279326983230456482242756608

Defined in Prettyprinter.Internal

Methods

pretty :: Integer -> Doc ann

prettyList :: [Integer] -> Doc ann

Pretty Natural

Defined in Prettyprinter.Internal

Methods

pretty :: Natural -> Doc ann

prettyList :: [Natural] -> Doc ann

Pretty Word

Defined in Prettyprinter.Internal

Methods

pretty :: Word -> Doc ann

prettyList :: [Word] -> Doc ann

Pretty Word8

Defined in Prettyprinter.Internal

Methods

pretty :: Word8 -> Doc ann

prettyList :: [Word8] -> Doc ann

Pretty Word16

Defined in Prettyprinter.Internal

Methods

pretty :: Word16 -> Doc ann

prettyList :: [Word16] -> Doc ann

Pretty Word32

Defined in Prettyprinter.Internal

Methods

pretty :: Word32 -> Doc ann

prettyList :: [Word32] -> Doc ann

Pretty Word64

Defined in Prettyprinter.Internal

Methods

pretty :: Word64 -> Doc ann

prettyList :: [Word64] -> Doc ann

Pretty ()

>>> pretty ()
()

The argument is not used:

>>> pretty (error "Strict?" :: ())
()

Defined in Prettyprinter.Internal

Methods

pretty :: () -> Doc ann

prettyList :: [()] -> Doc ann

Pretty Text

Automatically converts all newlines to line.

>>> pretty ("hello\nworld" :: Text)
hello
world

Note that line can be undone by group:

>>> group (pretty ("hello\nworld" :: Text))
hello world

Manually use hardline if you definitely want newlines.

Defined in Prettyprinter.Internal

Methods

pretty :: Text -> Doc ann

prettyList :: [Text] -> Doc ann

Pretty Text

(lazy Text instance, identical to the strict version)

Defined in Prettyprinter.Internal

Methods

pretty :: Text -> Doc ann

prettyList :: [Text] -> Doc ann

Pretty Void

Finding a good example for printing something that does not exist is hard, so here is an example of printing a list full of nothing.

>>> pretty ([] :: [Void])
[]

Defined in Prettyprinter.Internal

Methods

pretty :: Void -> Doc ann

prettyList :: [Void] -> Doc ann

Pretty Attributes

Defined in TPDB.Data.Attributes

Methods

pretty :: Attributes -> Doc ann

prettyList :: [Attributes] -> Doc ann

Pretty Identifier

Defined in TPDB.Plain.Write

Methods

pretty :: Identifier -> Doc ann

prettyList :: [Identifier] -> Doc ann

Pretty CertificationProblemInput

Defined in TPDB.CPF.Proof.Type

Methods

pretty :: CertificationProblemInput -> Doc ann

prettyList :: [CertificationProblemInput] -> Doc ann

Pretty a => Pretty [a]

>>> pretty [1,2,3]
[1, 2, 3]

Defined in Prettyprinter.Internal

Methods

pretty :: [a] -> Doc ann

prettyList :: [[a]] -> Doc ann

Pretty a => Pretty (Maybe a)

Ignore Nothings, print Just contents.

>>> pretty (Just True)
True
>>> braces (pretty (Nothing :: Maybe Bool))
{}

>>> pretty [Just 1, Nothing, Just 3, Nothing]
[1, 3]

Defined in Prettyprinter.Internal

Methods

pretty :: Maybe a -> Doc ann

prettyList :: [Maybe a] -> Doc ann

Pretty a => Pretty (Identity a)

>>> pretty (Identity 1)
1

Defined in Prettyprinter.Internal

Methods

pretty :: Identity a -> Doc ann

prettyList :: [Identity a] -> Doc ann

Pretty a => Pretty (NonEmpty a)

Defined in Prettyprinter.Internal

Methods

pretty :: NonEmpty a -> Doc ann

prettyList :: [NonEmpty a] -> Doc ann

PrettyTerm a => Pretty (Rule a)

Defined in TPDB.Plain.Write

Methods

pretty :: Rule a -> Doc ann

prettyList :: [Rule a] -> Doc ann

Pretty a => Pretty (Marked a)

Defined in TPDB.DP.Transform

Methods

pretty :: Marked a -> Doc ann

prettyList :: [Marked a] -> Doc ann

(Pretty a, Pretty b) => Pretty (Either a b)

WARNING: there is instance Pretty a => Pretty (Maybe a) in the back-end but its spec is "Ignore Nothings, print Just contents"

Defined in TPDB.Pretty

Methods

pretty :: Either a b -> Doc ann

prettyList :: [Either a b] -> Doc ann

(Pretty a1, Pretty a2) => Pretty (a1, a2)

>>> pretty (123, "hello")
(123, hello)

Defined in Prettyprinter.Internal

Methods

pretty :: (a1, a2) -> Doc ann

prettyList :: [(a1, a2)] -> Doc ann

(Pretty v, Pretty s) => Pretty (Term v s)

Defined in TPDB.Plain.Write

Methods

pretty :: Term v s -> Doc ann

prettyList :: [Term v s] -> Doc ann

(Pretty s, Pretty r, Variables (Term s r)) => Pretty (Problem s r)

Defined in TPDB.Plain.Write

Methods

pretty :: Problem s r -> Doc ann

prettyList :: [Problem s r] -> Doc ann

(Pretty s, PrettyTerm r, Variables (RS s r), Pretty (Var (RS s r))) => Pretty (RS s r)

Defined in TPDB.Plain.Write

Methods

pretty :: RS s r -> Doc ann

prettyList :: [RS s r] -> Doc ann

(Pretty a1, Pretty a2, Pretty a3) => Pretty (a1, a2, a3)

>>> pretty (123, "hello", False)
(123, hello, False)

Defined in Prettyprinter.Internal

Methods

pretty :: (a1, a2, a3) -> Doc ann

prettyList :: [(a1, a2, a3)] -> Doc ann

Pretty a => Pretty (Const a b)

Defined in Prettyprinter.Internal

Methods

pretty :: Const a b -> Doc ann

prettyList :: [Const a b] -> Doc ann

(Pretty a, Pretty b, Pretty c, Pretty d) => Pretty (a, b, c, d)

Defined in TPDB.Pretty

Methods

pretty :: (a, b, c, d) -> Doc ann

prettyList :: [(a, b, c, d)] -> Doc ann

render :: Doc ann -> Text

renderWide :: Doc ann -> SimpleDocStream ann

renderCompact :: Doc ann1 -> SimpleDocStream ann2

renderPretty :: Doc ann -> SimpleDocStream ann

displayIO :: Handle -> SimpleDocStream ann -> IO ()

fsep :: [Doc ann] -> Doc ann

sep :: [Doc ann] -> Doc ann

hsep :: [Doc ann] -> Doc ann

vsep :: [Doc ann] -> Doc ann

vcat :: [Doc ann] -> Doc ann

hcat :: [Doc ann] -> Doc ann

parens :: Doc ann -> Doc ann

>>> parens "·"
(·)

brackets :: Doc ann -> Doc ann

>>> brackets "·"
[·]

angles :: Doc ann -> Doc ann

>>> angles "·"
<·>

braces :: Doc ann -> Doc ann

>>> braces "·"
{·}

enclose

Arguments

:: Doc ann

L

-> Doc ann

R

-> Doc ann

x

-> Doc ann

LxR

(enclose l r x) encloses document x between documents l and r using <>.

>>> enclose "A" "Z" "·"
A·Z

enclose l r x = l <> x <> r

encloseSep

Arguments

:: Doc ann

left delimiter

-> Doc ann

right delimiter

-> Doc ann

separator

-> [Doc ann]

input documents

-> Doc ann

(encloseSep l r sep xs) concatenates the documents xs separated by sep, and encloses the resulting document by l and r.

The documents are laid out horizontally if that fits the page:

>>> let doc = "list" <+> align (encloseSep lbracket rbracket comma (map pretty [1,20,300,4000]))
>>> putDocW 80 doc
list [1,20,300,4000]

If there is not enough space, then the input is split into lines entry-wise therwise they are laid out vertically, with separators put in the front:

>>> putDocW 10 doc
list [1
     ,20
     ,300
     ,4000]

Note that doc contains an explicit call to align so that the list items are aligned vertically.

For putting separators at the end of entries instead, have a look at punctuate.

punctuate

Arguments

:: Doc ann

Punctuation, e.g. comma

-> [Doc ann]

-> [Doc ann]

(punctuate p xs) appends p to all but the last document in xs.

>>> let docs = punctuate comma (Util.words "lorem ipsum dolor sit amet")
>>> putDocW 80 (hsep docs)
lorem, ipsum, dolor, sit, amet

The separators are put at the end of the entries, which we can see if we position the result vertically:

>>> putDocW 20 (vsep docs)
lorem,
ipsum,
dolor,
sit,
amet

If you want put the commas in front of their elements instead of at the end, you should use tupled or, in general, encloseSep.

comma :: Doc ann

>>> comma
,

nest

Arguments

:: Int

Change of nesting level

-> Doc ann

-> Doc ann

(nest i x) lays out the document x with the current nesting level (indentation of the following lines) increased by i. Negative values are allowed, and decrease the nesting level accordingly.

>>> vsep [nest 4 (vsep ["lorem", "ipsum", "dolor"]), "sit", "amet"]
lorem
    ipsum
    dolor
sit
amet

See also

• hang (nest relative to current cursor position instead of current nesting level)
• align (set nesting level to current cursor position)
• indent (increase indentation on the spot, padding with spaces).

list :: [Doc ann] -> Doc ann

Haskell-inspired variant of encloseSep with braces and comma as separator.

>>> let doc = list (map pretty [1,20,300,4000])

>>> putDocW 80 doc
[1, 20, 300, 4000]

>>> putDocW 10 doc
[ 1
, 20
, 300
, 4000 ]

tupled :: [Doc ann] -> Doc ann

Haskell-inspired variant of encloseSep with parentheses and comma as separator.

>>> let doc = tupled (map pretty [1,20,300,4000])

>>> putDocW 80 doc
(1, 20, 300, 4000)

>>> putDocW 10 doc
( 1
, 20
, 300
, 4000 )

(<>) :: Semigroup a => a -> a -> a infixr 6

An associative operation.

>>> [1,2,3] <> [4,5,6]
[1,2,3,4,5,6]

mempty :: Monoid a => a

Identity of mappend

>>> "Hello world" <> mempty
"Hello world"

empty :: Doc ann

text :: String -> Doc ann

(<+>) :: Doc ann -> Doc ann -> Doc ann

($$) :: Doc ann -> Doc ann -> Doc ann

indent

Arguments

:: Int

Number of spaces to increase indentation by

-> Doc ann

-> Doc ann

(indent i x) indents document x by i columns, starting from the current cursor position.

>>> let doc = reflow "The indent function indents these words!"
>>> putDocW 24 ("prefix" <> indent 4 doc)
prefix    The indent
          function
          indents these
          words!

indent i d = hang i ({i spaces} <> d)

nest

Arguments

:: Int

Change of nesting level

-> Doc ann

-> Doc ann

(nest i x) lays out the document x with the current nesting level (indentation of the following lines) increased by i. Negative values are allowed, and decrease the nesting level accordingly.

>>> vsep [nest 4 (vsep ["lorem", "ipsum", "dolor"]), "sit", "amet"]
lorem
    ipsum
    dolor
sit
amet

See also

• hang (nest relative to current cursor position instead of current nesting level)
• align (set nesting level to current cursor position)
• indent (increase indentation on the spot, padding with spaces).

hang

Arguments

:: Int

Change of nesting level, relative to the start of the first line

-> Doc ann

-> Doc ann

(hang i x) lays out the document x with a nesting level set to the current column plus i. Negative values are allowed, and decrease the nesting level accordingly.

>>> let doc = reflow "Indenting these words with hang"
>>> putDocW 24 ("prefix" <+> hang 4 doc)
prefix Indenting these
           words with
           hang

This differs from nest, which is based on the current nesting level plus i. When you're not sure, try the more efficient nest first. In our example, this would yield

>>> let doc = reflow "Indenting these words with nest"
>>> putDocW 24 ("prefix" <+> nest 4 doc)
prefix Indenting these
    words with nest

hang i doc = align (nest i doc)

Orphan instances

(Pretty a, Pretty b) => Pretty (Either a b)

WARNING: there is instance Pretty a => Pretty (Maybe a) in the back-end but its spec is "Ignore Nothings, print Just contents"

Methods

pretty :: Either a b -> Doc ann

prettyList :: [Either a b] -> Doc ann

(Pretty a, Pretty b, Pretty c, Pretty d) => Pretty (a, b, c, d)

Methods

pretty :: (a, b, c, d) -> Doc ann

prettyList :: [(a, b, c, d)] -> Doc ann