Distribution.Fields.Parser

Types

data Field ann

A Cabal-like file consists of a series of fields (foo: bar) and sections (library ...).

Constructors

Field !(Name ann) [FieldLine ann]

Section !(Name ann) [SectionArg ann] [Field ann]

Instances

Foldable Field

Defined in Distribution.Fields.Field

Methods

fold :: Monoid m => Field m -> m

foldMap :: Monoid m => (a -> m) -> Field a -> m

foldMap' :: Monoid m => (a -> m) -> Field a -> m

foldr :: (a -> b -> b) -> b -> Field a -> b

foldr' :: (a -> b -> b) -> b -> Field a -> b

foldl :: (b -> a -> b) -> b -> Field a -> b

foldl' :: (b -> a -> b) -> b -> Field a -> b

foldr1 :: (a -> a -> a) -> Field a -> a

foldl1 :: (a -> a -> a) -> Field a -> a

toList :: Field a -> [a]

null :: Field a -> Bool

length :: Field a -> Int

elem :: Eq a => a -> Field a -> Bool

maximum :: Ord a => Field a -> a

minimum :: Ord a => Field a -> a

sum :: Num a => Field a -> a

product :: Num a => Field a -> a

Foldable1 Field

Since: 3.12.0.0

Defined in Distribution.Fields.Field

Methods

fold1 :: Semigroup m => Field m -> m

foldMap1 :: Semigroup m => (a -> m) -> Field a -> m

foldMap1' :: Semigroup m => (a -> m) -> Field a -> m

toNonEmpty :: Field a -> NonEmpty a

maximum :: Ord a => Field a -> a

minimum :: Ord a => Field a -> a

head :: Field a -> a

last :: Field a -> a

foldrMap1 :: (a -> b) -> (a -> b -> b) -> Field a -> b

foldlMap1' :: (a -> b) -> (b -> a -> b) -> Field a -> b

foldlMap1 :: (a -> b) -> (b -> a -> b) -> Field a -> b

foldrMap1' :: (a -> b) -> (a -> b -> b) -> Field a -> b

Traversable Field

Defined in Distribution.Fields.Field

Methods

traverse :: Applicative f => (a -> f b) -> Field a -> f (Field b)

sequenceA :: Applicative f => Field (f a) -> f (Field a)

mapM :: Monad m => (a -> m b) -> Field a -> m (Field b)

sequence :: Monad m => Field (m a) -> m (Field a)

Functor Field

Defined in Distribution.Fields.Field

Methods

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

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

Show ann => Show (Field ann)

Defined in Distribution.Fields.Field

Methods

showsPrec :: Int -> Field ann -> ShowS

show :: Field ann -> String

showList :: [Field ann] -> ShowS

Eq ann => Eq (Field ann)

Defined in Distribution.Fields.Field

Methods

(==) :: Field ann -> Field ann -> Bool

(/=) :: Field ann -> Field ann -> Bool

Ord ann => Ord (Field ann)

Since: 3.12.0.0

Defined in Distribution.Fields.Field

Methods

compare :: Field ann -> Field ann -> Ordering

(<) :: Field ann -> Field ann -> Bool

(<=) :: Field ann -> Field ann -> Bool

(>) :: Field ann -> Field ann -> Bool

(>=) :: Field ann -> Field ann -> Bool

max :: Field ann -> Field ann -> Field ann

min :: Field ann -> Field ann -> Field ann

data Name ann

A field name.

Invariant: ByteString is lower-case ASCII.

Constructors

Name !ann !FieldName

Instances

Foldable Name

Defined in Distribution.Fields.Field

Methods

fold :: Monoid m => Name m -> m

foldMap :: Monoid m => (a -> m) -> Name a -> m

foldMap' :: Monoid m => (a -> m) -> Name a -> m

foldr :: (a -> b -> b) -> b -> Name a -> b

foldr' :: (a -> b -> b) -> b -> Name a -> b

foldl :: (b -> a -> b) -> b -> Name a -> b

foldl' :: (b -> a -> b) -> b -> Name a -> b

foldr1 :: (a -> a -> a) -> Name a -> a

foldl1 :: (a -> a -> a) -> Name a -> a

toList :: Name a -> [a]

null :: Name a -> Bool

length :: Name a -> Int

elem :: Eq a => a -> Name a -> Bool

maximum :: Ord a => Name a -> a

minimum :: Ord a => Name a -> a

sum :: Num a => Name a -> a

product :: Num a => Name a -> a

Foldable1 Name

Since: 3.12.0.0

Defined in Distribution.Fields.Field

Methods

fold1 :: Semigroup m => Name m -> m

foldMap1 :: Semigroup m => (a -> m) -> Name a -> m

foldMap1' :: Semigroup m => (a -> m) -> Name a -> m

toNonEmpty :: Name a -> NonEmpty a

maximum :: Ord a => Name a -> a

minimum :: Ord a => Name a -> a

head :: Name a -> a

last :: Name a -> a

foldrMap1 :: (a -> b) -> (a -> b -> b) -> Name a -> b

foldlMap1' :: (a -> b) -> (b -> a -> b) -> Name a -> b

foldlMap1 :: (a -> b) -> (b -> a -> b) -> Name a -> b

foldrMap1' :: (a -> b) -> (a -> b -> b) -> Name a -> b

Traversable Name

Defined in Distribution.Fields.Field

Methods

traverse :: Applicative f => (a -> f b) -> Name a -> f (Name b)

sequenceA :: Applicative f => Name (f a) -> f (Name a)

mapM :: Monad m => (a -> m b) -> Name a -> m (Name b)

sequence :: Monad m => Name (m a) -> m (Name a)

Functor Name

Defined in Distribution.Fields.Field

Methods

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

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

Show ann => Show (Name ann)

Defined in Distribution.Fields.Field

Methods

showsPrec :: Int -> Name ann -> ShowS

show :: Name ann -> String

showList :: [Name ann] -> ShowS

Eq ann => Eq (Name ann)

Defined in Distribution.Fields.Field

Methods

(==) :: Name ann -> Name ann -> Bool

(/=) :: Name ann -> Name ann -> Bool

Ord ann => Ord (Name ann)

Since: 3.12.0.0

Defined in Distribution.Fields.Field

Methods

compare :: Name ann -> Name ann -> Ordering

(<) :: Name ann -> Name ann -> Bool

(<=) :: Name ann -> Name ann -> Bool

(>) :: Name ann -> Name ann -> Bool

(>=) :: Name ann -> Name ann -> Bool

max :: Name ann -> Name ann -> Name ann

min :: Name ann -> Name ann -> Name ann

data FieldLine ann

A line of text representing the value of a field from a Cabal file. A field may contain multiple lines.

Invariant: ByteString has no newlines.

Constructors

FieldLine !ann !ByteString

Instances

Foldable FieldLine

Defined in Distribution.Fields.Field

Methods

fold :: Monoid m => FieldLine m -> m

foldMap :: Monoid m => (a -> m) -> FieldLine a -> m

foldMap' :: Monoid m => (a -> m) -> FieldLine a -> m

foldr :: (a -> b -> b) -> b -> FieldLine a -> b

foldr' :: (a -> b -> b) -> b -> FieldLine a -> b

foldl :: (b -> a -> b) -> b -> FieldLine a -> b

foldl' :: (b -> a -> b) -> b -> FieldLine a -> b

foldr1 :: (a -> a -> a) -> FieldLine a -> a

foldl1 :: (a -> a -> a) -> FieldLine a -> a

toList :: FieldLine a -> [a]

null :: FieldLine a -> Bool

length :: FieldLine a -> Int

elem :: Eq a => a -> FieldLine a -> Bool

maximum :: Ord a => FieldLine a -> a

minimum :: Ord a => FieldLine a -> a

sum :: Num a => FieldLine a -> a

product :: Num a => FieldLine a -> a

Foldable1 FieldLine

Since: 3.12.0.0

Defined in Distribution.Fields.Field

Methods

fold1 :: Semigroup m => FieldLine m -> m

foldMap1 :: Semigroup m => (a -> m) -> FieldLine a -> m

foldMap1' :: Semigroup m => (a -> m) -> FieldLine a -> m

toNonEmpty :: FieldLine a -> NonEmpty a

maximum :: Ord a => FieldLine a -> a

minimum :: Ord a => FieldLine a -> a

head :: FieldLine a -> a

last :: FieldLine a -> a

foldrMap1 :: (a -> b) -> (a -> b -> b) -> FieldLine a -> b

foldlMap1' :: (a -> b) -> (b -> a -> b) -> FieldLine a -> b

foldlMap1 :: (a -> b) -> (b -> a -> b) -> FieldLine a -> b

foldrMap1' :: (a -> b) -> (a -> b -> b) -> FieldLine a -> b

Traversable FieldLine

Defined in Distribution.Fields.Field

Methods

traverse :: Applicative f => (a -> f b) -> FieldLine a -> f (FieldLine b)

sequenceA :: Applicative f => FieldLine (f a) -> f (FieldLine a)

mapM :: Monad m => (a -> m b) -> FieldLine a -> m (FieldLine b)

sequence :: Monad m => FieldLine (m a) -> m (FieldLine a)

Functor FieldLine

Defined in Distribution.Fields.Field

Methods

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

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

Show ann => Show (FieldLine ann)

Defined in Distribution.Fields.Field

Methods

showsPrec :: Int -> FieldLine ann -> ShowS

show :: FieldLine ann -> String

showList :: [FieldLine ann] -> ShowS

Eq ann => Eq (FieldLine ann)

Defined in Distribution.Fields.Field

Methods

(==) :: FieldLine ann -> FieldLine ann -> Bool

(/=) :: FieldLine ann -> FieldLine ann -> Bool

Ord ann => Ord (FieldLine ann)

Since: 3.12.0.0

Defined in Distribution.Fields.Field

Methods

compare :: FieldLine ann -> FieldLine ann -> Ordering

(<) :: FieldLine ann -> FieldLine ann -> Bool

(<=) :: FieldLine ann -> FieldLine ann -> Bool

(>) :: FieldLine ann -> FieldLine ann -> Bool

(>=) :: FieldLine ann -> FieldLine ann -> Bool

max :: FieldLine ann -> FieldLine ann -> FieldLine ann

min :: FieldLine ann -> FieldLine ann -> FieldLine ann

data SectionArg ann

Section arguments, e.g. name of the library

Constructors

SecArgName !ann !ByteString

identifier, or something which looks like number. Also many dot numbers, i.e. "7.6.3"

SecArgStr !ann !ByteString

quoted string

SecArgOther !ann !ByteString

everything else, mm. operators (e.g. in if-section conditionals)

Instances

Foldable SectionArg

Defined in Distribution.Fields.Field

Methods

fold :: Monoid m => SectionArg m -> m

foldMap :: Monoid m => (a -> m) -> SectionArg a -> m

foldMap' :: Monoid m => (a -> m) -> SectionArg a -> m

foldr :: (a -> b -> b) -> b -> SectionArg a -> b

foldr' :: (a -> b -> b) -> b -> SectionArg a -> b

foldl :: (b -> a -> b) -> b -> SectionArg a -> b

foldl' :: (b -> a -> b) -> b -> SectionArg a -> b

foldr1 :: (a -> a -> a) -> SectionArg a -> a

foldl1 :: (a -> a -> a) -> SectionArg a -> a

toList :: SectionArg a -> [a]

null :: SectionArg a -> Bool

length :: SectionArg a -> Int

elem :: Eq a => a -> SectionArg a -> Bool

maximum :: Ord a => SectionArg a -> a

minimum :: Ord a => SectionArg a -> a

sum :: Num a => SectionArg a -> a

product :: Num a => SectionArg a -> a

Foldable1 SectionArg

Since: 3.12.0.0

Defined in Distribution.Fields.Field

Methods

fold1 :: Semigroup m => SectionArg m -> m

foldMap1 :: Semigroup m => (a -> m) -> SectionArg a -> m

foldMap1' :: Semigroup m => (a -> m) -> SectionArg a -> m

toNonEmpty :: SectionArg a -> NonEmpty a

maximum :: Ord a => SectionArg a -> a

minimum :: Ord a => SectionArg a -> a

head :: SectionArg a -> a

last :: SectionArg a -> a

foldrMap1 :: (a -> b) -> (a -> b -> b) -> SectionArg a -> b

foldlMap1' :: (a -> b) -> (b -> a -> b) -> SectionArg a -> b

foldlMap1 :: (a -> b) -> (b -> a -> b) -> SectionArg a -> b

foldrMap1' :: (a -> b) -> (a -> b -> b) -> SectionArg a -> b

Traversable SectionArg

Defined in Distribution.Fields.Field

Methods

traverse :: Applicative f => (a -> f b) -> SectionArg a -> f (SectionArg b)

sequenceA :: Applicative f => SectionArg (f a) -> f (SectionArg a)

mapM :: Monad m => (a -> m b) -> SectionArg a -> m (SectionArg b)

sequence :: Monad m => SectionArg (m a) -> m (SectionArg a)

Functor SectionArg

Defined in Distribution.Fields.Field

Methods

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

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

Show ann => Show (SectionArg ann)

Defined in Distribution.Fields.Field

Methods

showsPrec :: Int -> SectionArg ann -> ShowS

show :: SectionArg ann -> String

showList :: [SectionArg ann] -> ShowS

Eq ann => Eq (SectionArg ann)

Defined in Distribution.Fields.Field

Methods

(==) :: SectionArg ann -> SectionArg ann -> Bool

(/=) :: SectionArg ann -> SectionArg ann -> Bool

Ord ann => Ord (SectionArg ann)

Since: 3.12.0.0

Defined in Distribution.Fields.Field

Methods

compare :: SectionArg ann -> SectionArg ann -> Ordering

(<) :: SectionArg ann -> SectionArg ann -> Bool

(<=) :: SectionArg ann -> SectionArg ann -> Bool

(>) :: SectionArg ann -> SectionArg ann -> Bool

(>=) :: SectionArg ann -> SectionArg ann -> Bool

max :: SectionArg ann -> SectionArg ann -> SectionArg ann

min :: SectionArg ann -> SectionArg ann -> SectionArg ann

Grammar and parsing

CabalStyleFile ::= SecElems

SecElems       ::= SecElem* '\n'?
SecElem        ::= '\n' SecElemLayout | SecElemBraces
SecElemLayout  ::= FieldLayout | FieldBraces | SectionLayout | SectionBraces
SecElemBraces  ::= FieldInline | FieldBraces |                 SectionBraces
FieldLayout    ::= name : line? ('\n' line)*
FieldBraces    ::= name : '\n'? '{' content '}'
FieldInline    ::= name : content
SectionLayout  ::= name arg* SecElems
SectionBraces  ::= name arg* '\n'? '{' SecElems '}'

and the same thing but left factored...

SecElems              ::= SecElem*
SecElem               ::= '\n' name SecElemLayout
                        |      name SecElemBraces
SecElemLayout         ::= :   FieldLayoutOrBraces
                        | arg*  SectionLayoutOrBraces
FieldLayoutOrBraces   ::= '\n'? '{' content '}'
                        | line? ('\n' line)*
SectionLayoutOrBraces ::= '\n'? '{' SecElems '\n'? '}'
                        | SecElems
SecElemBraces         ::= : FieldInlineOrBraces
                        | arg* '\n'? '{' SecElems '\n'? '}'
FieldInlineOrBraces   ::= '\n'? '{' content '}'
                        | content

Note how we have several productions with the sequence:

'\\n'? '{'

That is, an optional newline (and indent) followed by a { token. In the SectionLayoutOrBraces case you can see that this makes it not fully left factored (because SecElems can start with a \n). Fully left factoring here would be ugly, and though we could use a lookahead of two tokens to resolve the alternatives, we can't conveniently use Parsec's try here to get a lookahead of only two. So instead we deal with this case in the lexer by making a line where the first non-space is { lex as just the { token, without the usual indent token. Then in the parser we can resolve everything with just one token of lookahead and so without using try.

readFields :: ByteString -> Either ParseError [Field Position]

Parse cabal style ByteString into list of Fields, i.e. the cabal AST.

readFields assumes that input ByteString is valid UTF8, specifically it doesn't validate that file is valid UTF8. Therefore bytestrings inside returned Field will be invalid as UTF8 if the input were.

>>> readFields "foo: \223"
Right [Field (Name (Position 1 1) "foo") [FieldLine (Position 1 6) "\223"]]

readFields won't (necessarily) fail on invalid UTF8 data, but the reported positions may be off.

You may get weird errors on non-UTF8 input, for example readFields will fail on latin1 encoded non-breaking space:

>>> isLeft (readFields "\xa0 foo: bar")
True

That is rejected because parser thinks \xa0 is a section name, and section arguments may not contain colon. If there are just latin1 non-breaking spaces, they become part of the name:

>>> readFields "\xa0\&foo: bar"
Right [Field (Name (Position 1 1) "\160foo") [FieldLine (Position 1 7) "bar"]]

The UTF8 non-breaking space is accepted as an indentation character (but warned about by readFields').

>>> readFields' "\xc2\xa0 foo: bar"
Right ([Field (Name (Position 1 3) "foo") [FieldLine (Position 1 8) "bar"]],[LexWarning LexWarningNBSP (Position 1 1)])

readFields' :: ByteString -> Either ParseError ([Field Position], [LexWarning])

Like readFields but also return lexer warnings.