Dhall.Pretty

This module contains logic for pretty-printing expressions, including support for syntax highlighting

Pretty

data Ann

Annotation type used to tag elements in a pretty-printed document for syntax highlighting purposes

Constructors

Keyword

Used for syntactic keywords

Syntax

Syntax punctuation such as commas, parenthesis, and braces

Label

Record labels

Literal

Literals such as integers and strings

Builtin

Builtin types and values

Operator

Operators

Instances

Show Ann

Defined in Dhall.Pretty.Internal

Methods

showsPrec :: Int -> Ann -> ShowS

show :: Ann -> String

showList :: [Ann] -> ShowS

annToAnsiStyle :: Ann -> AnsiStyle

Convert annotations to their corresponding color for syntax highlighting purposes

prettyExpr :: Pretty a => Expr s a -> Doc Ann

Pretty print an expression

data CharacterSet

This type determines whether to render code as ASCII or Unicode

Constructors

ASCII

Unicode

Instances

Show CharacterSet

Defined in Dhall.Pretty.Internal

Methods

showsPrec :: Int -> CharacterSet -> ShowS

show :: CharacterSet -> String

showList :: [CharacterSet] -> ShowS

prettyCharacterSet :: Pretty a => CharacterSet -> Expr Src a -> Doc Ann

Pretty-print an Expr using the given CharacterSet.

prettyCharacterSet largely ignores Notes. Notes do however matter for the layout of let-blocks:

>>> let inner = Let (Binding Nothing "x" Nothing Nothing Nothing (NaturalLit 1)) (Var (V "x" 0)) :: Expr Src ()
>>> prettyCharacterSet ASCII (Let (Binding Nothing "y" Nothing Nothing Nothing (NaturalLit 2)) inner)
let y = 2 let x = 1 in x
>>> prettyCharacterSet ASCII (Let (Binding Nothing "y" Nothing Nothing Nothing (NaturalLit 2)) (Note (Src unusedSourcePos unusedSourcePos "") inner))
let y = 2 in let x = 1 in x

This means the structure of parsed let-blocks is preserved.

layout :: Doc ann -> SimpleDocStream ann

Layout using layoutOpts

Tries hard to fit the document into 80 columns.

This also removes trailing space characters (' ') unless they are enclosed in an annotation.

layoutOpts :: LayoutOptions

Default layout options

escapeEnvironmentVariable :: Text -> Text

Escape an environment variable if not a valid Bash environment variable

escapeLabel :: Bool -> Text -> Text

Escape a label if it is not valid when unquoted