Data.Generics.Fixplate.Pretty

Generic pretty-printing of expression trees.

TODO:

• make the style configurable (so that we can print the same expression in different formats) (in Haskell98, we have to use the record instead of class trick for this?)
• corresponding parser?

Documentation

data Assoc

Associativity

Constructors

NoAssoc

LeftAssoc

RightAssoc

Instances

Eq Assoc

Methods

(==) :: Assoc -> Assoc -> Bool

(/=) :: Assoc -> Assoc -> Bool

Show Assoc

Methods

showsPrec :: Int -> Assoc -> ShowS

show :: Assoc -> String

showList :: [Assoc] -> ShowS

data Bracket

A pair of matching brackets, eg. Bracket "(" ")" or Bracket "[|" "|]".

Constructors

Bracket !String !String

Instances

Eq Bracket

Methods

(==) :: Bracket -> Bracket -> Bool

(/=) :: Bracket -> Bracket -> Bool

Show Bracket

Methods

showsPrec :: Int -> Bracket -> ShowS

show :: Bracket -> String

showList :: [Bracket] -> ShowS

type Separator = String

A separator, eg. "," or " | ".

data AppStyle

Application style

Constructors

Haskell

eg. (Node arg1 arg2 arg3); precedence will be app_prec == 10

Algol !Bracket !Separator

eg. node[arg1,arg2,arg3]; precedence will be 11, but child environment precedence will be 0

Instances

Eq AppStyle

Methods

(==) :: AppStyle -> AppStyle -> Bool

(/=) :: AppStyle -> AppStyle -> Bool

Show AppStyle

Methods

showsPrec :: Int -> AppStyle -> ShowS

show :: AppStyle -> String

showList :: [AppStyle] -> ShowS

data MixWord

Mixfix style. Example:

[ Keyword "if" , Placeholder , keyword "then" , Placeholder , keyword "else" , Placeholder ]

Constructors

Keyword String

Placeholder

Instances

Eq MixWord

Methods

(==) :: MixWord -> MixWord -> Bool

(/=) :: MixWord -> MixWord -> Bool

Show MixWord

Methods

showsPrec :: Int -> MixWord -> ShowS

show :: MixWord -> String

showList :: [MixWord] -> ShowS

mixWords :: [MixWord] -> [ShowS] -> ShowS

data Fixity

Fixities. TODO: separate non-fixity stuff like style and words

Constructors

Atom

eg. variable; precedence will be 666

Application !AppStyle

eg. (Node arg1 arg2 arg3) or node[arg1,arg2,arg3].

Prefix !Int

eg. ~arg; the Int is the precendence

Infix !Assoc !Int

eg. x+y

Postfix !Int

eg. arg++

Mixfix [MixWord]

eg. if ... then ... else ... or let ... in .... With precedence 0?

Custom !Int

for your custom rendering

Instances

Eq Fixity

Methods

(==) :: Fixity -> Fixity -> Bool

(/=) :: Fixity -> Fixity -> Bool

Show Fixity

Methods

showsPrec :: Int -> Fixity -> ShowS

show :: Fixity -> String

showList :: [Fixity] -> ShowS

fixityPrecedence :: Fixity -> Int

class (Functor f, Foldable f) => Pretty f where

A class encoding fixity and rendering of nodes if the tree.

Minimum complete definition: fixity, and showNode or showsPrecNode. Unless you want some type of rendering not directly supported, you shouldn't specify showsPrecNode.

Minimal complete definition

fixity, showNode

Methods

fixity :: f a -> Fixity

fixity of the node

showNode :: f a -> String

a string representing the node without the children

showsPrecNode :: (Int -> a -> ShowS) -> Int -> f a -> ShowS

full rendering of the node. You can redefine this for custom renderings.

pretty :: Pretty f => Mu f -> String

Render the expression

prettyS :: Pretty f => Mu f -> ShowS

prettyPrec :: Pretty f => Int -> Mu f -> ShowS