Dhall.Parser

This module contains Dhall's parsing logic

Utilities

exprFromText

Arguments

:: String

User-friendly name describing the input expression, used in parsing error messages

-> Text

Input expression to parse

-> Either ParseError (Expr Src Import)

Parse an expression from Expr containing a Dhall program

exprAndHeaderFromText

Arguments

:: String

User-friendly name describing the input expression, used in parsing error messages

-> Text

Input expression to parse

-> Either ParseError (Header, Expr Src Import)

Like exprFromText but also returns the leading comments and whitespace (i.e. header) up to the last newline before the code begins

In other words, if you have a Dhall file of the form:

-- Comment 1
{- Comment -} 2

Then this will preserve Comment 1, but not Comment 2

This is used by dhall-format to preserve leading comments and whitespace

censor :: ParseError -> ParseError

Replace the source code with spaces when rendering error messages

This utility is used to implement the --censor flag

createHeader :: Text -> Header

Create a header with stripped leading spaces and trailing newlines

Parsers

expr :: Parser (Expr Src Import)

Parser for a top-level Dhall expression

exprA :: Parser a -> Parser (Expr Src a)

Deprecated: Support for parsing custom imports will be dropped in a future release

Parser for a top-level Dhall expression. The expression is parameterized over any parseable type, allowing the language to be extended as needed.

Types

newtype Header

A header corresponds to the leading comment at the top of a Dhall file.

The header includes comment characters but is stripped of leading spaces and trailing newlines

Constructors

Header Text

Instances

Show Header

Defined in Dhall.Parser

Methods

showsPrec :: Int -> Header -> ShowS

show :: Header -> String

showList :: [Header] -> ShowS

data Src

Source code extract

Constructors

Src

Fields

• srcStart :: !SourcePos
• srcEnd :: !SourcePos
• srcText :: Text

Instances

Eq Src

Defined in Dhall.Src

Methods

(==) :: Src -> Src -> Bool

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

Data Src

Defined in Dhall.Src

Methods

gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Src -> c Src

gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c Src

toConstr :: Src -> Constr

dataTypeOf :: Src -> DataType

dataCast1 :: Typeable t => (forall d. Data d => c (t d)) -> Maybe (c Src)

dataCast2 :: Typeable t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c Src)

gmapT :: (forall b. Data b => b -> b) -> Src -> Src

gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Src -> r

gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Src -> r

gmapQ :: (forall d. Data d => d -> u) -> Src -> [u]

gmapQi :: Int -> (forall d. Data d => d -> u) -> Src -> u

gmapM :: Monad m => (forall d. Data d => d -> m d) -> Src -> m Src

gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Src -> m Src

gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Src -> m Src

Ord Src

Defined in Dhall.Src

Methods

compare :: Src -> Src -> Ordering

(<) :: Src -> Src -> Bool

(<=) :: Src -> Src -> Bool

(>) :: Src -> Src -> Bool

(>=) :: Src -> Src -> Bool

max :: Src -> Src -> Src

min :: Src -> Src -> Src

Show Src

Defined in Dhall.Src

Methods

showsPrec :: Int -> Src -> ShowS

show :: Src -> String

showList :: [Src] -> ShowS

Generic Src

Defined in Dhall.Src

Associated Types

type Rep Src :: Type -> Type

Methods

from :: Src -> Rep Src x

to :: Rep Src x -> Src

Lift Src

Defined in Dhall.Src

Methods

lift :: Src -> Q Exp

NFData Src

Defined in Dhall.Src

Methods

rnf :: Src -> ()

Pretty Src

Defined in Dhall.Src

Methods

pretty :: Src -> Doc ann

prettyList :: [Src] -> Doc ann

type Rep Src

Defined in Dhall.Src

type Rep Src = D1 (MetaData "Src" "Dhall.Src" "dhall-1.32.0-90ekLWlfiRUK7vmmlOVhVv" False) (C1 (MetaCons "Src" PrefixI True) (S1 (MetaSel (Just "srcStart") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 SourcePos) :*: (S1 (MetaSel (Just "srcEnd") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 SourcePos) :*: S1 (MetaSel (Just "srcText") NoSourceUnpackedness NoSourceStrictness DecidedLazy) (Rec0 Text))))

data SourcedException e

An exception annotated with a Src span

Constructors

SourcedException Src e

Instances

Show e => Show (SourcedException e)

Defined in Dhall.Parser.Combinators

Methods

showsPrec :: Int -> SourcedException e -> ShowS

show :: SourcedException e -> String

showList :: [SourcedException e] -> ShowS

Exception e => Exception (SourcedException e)

Defined in Dhall.Parser.Combinators

Methods

toException :: SourcedException e -> SomeException

fromException :: SomeException -> Maybe (SourcedException e)

displayException :: SourcedException e -> String

data ParseError

A parsing error

Constructors

ParseError

Fields

• unwrap :: ParseErrorBundle Text Void
• input :: Text

Instances

Show ParseError

Defined in Dhall.Parser

Methods

showsPrec :: Int -> ParseError -> ShowS

show :: ParseError -> String

showList :: [ParseError] -> ShowS

Exception ParseError

Defined in Dhall.Parser

Methods

toException :: ParseError -> SomeException

fromException :: SomeException -> Maybe ParseError

displayException :: ParseError -> String

newtype Parser a

A Parser that is almost identical to Text.Megaparsec.Parsec except treating Haskell-style comments as whitespace

Constructors

Parser

Fields

• unParser :: Parsec Void Text a

Instances

Monad Parser

Defined in Dhall.Parser.Combinators

Methods

(>>=) :: Parser a -> (a -> Parser b) -> Parser b

(>>) :: Parser a -> Parser b -> Parser b

return :: a -> Parser a

fail :: String -> Parser a

Functor Parser

Defined in Dhall.Parser.Combinators

Methods

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

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

MonadFail Parser

Defined in Dhall.Parser.Combinators

Methods

fail :: String -> Parser a

Applicative Parser

Defined in Dhall.Parser.Combinators

Methods

pure :: a -> Parser a

(<*>) :: Parser (a -> b) -> Parser a -> Parser b

liftA2 :: (a -> b -> c) -> Parser a -> Parser b -> Parser c

(*>) :: Parser a -> Parser b -> Parser b

(<*) :: Parser a -> Parser b -> Parser a

Alternative Parser

Defined in Dhall.Parser.Combinators

Methods

empty :: Parser a

(<|>) :: Parser a -> Parser a -> Parser a

some :: Parser a -> Parser [a]

many :: Parser a -> Parser [a]

MonadPlus Parser

Defined in Dhall.Parser.Combinators

Methods

mzero :: Parser a

mplus :: Parser a -> Parser a -> Parser a

TokenParsing Parser

Defined in Dhall.Parser.Combinators

Methods

someSpace :: Parser ()

nesting :: Parser a -> Parser a

semi :: Parser Char

highlight :: Highlight -> Parser a -> Parser a

token :: Parser a -> Parser a

CharParsing Parser

Defined in Dhall.Parser.Combinators

Methods

satisfy :: (Char -> Bool) -> Parser Char

char :: Char -> Parser Char

notChar :: Char -> Parser Char

anyChar :: Parser Char

string :: String -> Parser String

text :: Text -> Parser Text

Parsing Parser

Defined in Dhall.Parser.Combinators

Methods

try :: Parser a -> Parser a

(<?>) :: Parser a -> String -> Parser a

skipMany :: Parser a -> Parser ()

skipSome :: Parser a -> Parser ()

unexpected :: String -> Parser a

eof :: Parser ()

notFollowedBy :: Show a => Parser a -> Parser ()

MonadParsec Void Text Parser

Defined in Dhall.Parser.Combinators

Methods

parseError :: ParseError Text Void -> Parser a

label :: String -> Parser a -> Parser a

hidden :: Parser a -> Parser a

try :: Parser a -> Parser a

lookAhead :: Parser a -> Parser a

notFollowedBy :: Parser a -> Parser ()

withRecovery :: (ParseError Text Void -> Parser a) -> Parser a -> Parser a

observing :: Parser a -> Parser (Either (ParseError Text Void) a)

eof :: Parser ()

token :: (Token Text -> Maybe a) -> Set (ErrorItem (Token Text)) -> Parser a

tokens :: (Tokens Text -> Tokens Text -> Bool) -> Tokens Text -> Parser (Tokens Text)

takeWhileP :: Maybe String -> (Token Text -> Bool) -> Parser (Tokens Text)

takeWhile1P :: Maybe String -> (Token Text -> Bool) -> Parser (Tokens Text)

takeP :: Maybe String -> Int -> Parser (Tokens Text)

getParserState :: Parser (State Text Void)

updateParserState :: (State Text Void -> State Text Void) -> Parser ()

IsString a => IsString (Parser a)

Defined in Dhall.Parser.Combinators

Methods

fromString :: String -> Parser a

Semigroup a => Semigroup (Parser a)

Defined in Dhall.Parser.Combinators

Methods

(<>) :: Parser a -> Parser a -> Parser a

sconcat :: NonEmpty (Parser a) -> Parser a

stimes :: Integral b => b -> Parser a -> Parser a

(Semigroup a, Monoid a) => Monoid (Parser a)

Defined in Dhall.Parser.Combinators

Methods

mempty :: Parser a

mappend :: Parser a -> Parser a -> Parser a

mconcat :: [Parser a] -> Parser a