<?> -package:parsers

(<?>) :: Parser a -> JSONPathElement -> Parser a
aeson Data.Aeson Data.Aeson.Types
Add JSON Path context to a parser When parsing a complex structure, it helps to annotate (sub)parsers with context, so that if an error occurs, you can find its location. 
withObject "Person" $ \o ->
Person
<$> o .: "name" <?> Key "name"
<*> o .: "age"  <?> Key "age"
(Standard methods like (.:) already do this.) With such annotations, if an error occurs, you will get a JSON Path location of that error. Since 0.10
(<?>) :: ParsecT s u m a -> String -> ParsecT s u m a
parsec Text.Parsec Text.Parsec.Prim Text.ParserCombinators.Parsec.Prim
The parser p <?> msg behaves as parser p, but whenever the parser p fails without consuming any input, it replaces expect error messages with the expect error message msg. This is normally used at the end of a set alternatives where we want to return an error message in terms of a higher level construct rather than returning all possible characters. For example, if the expr parser from the try example would fail, the error message is: '...: expecting expression'. Without the (<?>) combinator, the message would be like '...: expecting "let" or letter', which is less friendly.
(<?>) :: Parser i a -> String -> Parser i a
attoparsec Data.Attoparsec.ByteString Data.Attoparsec.ByteString.Char8 Data.Attoparsec.ByteString.Lazy Data.Attoparsec.Combinator Data.Attoparsec.Text Data.Attoparsec.Text.Lazy
Name the parser, in case failure occurs.
(<?>) :: MonadParsec e s m => m a -> String -> m a
megaparsec Text.Megaparsec
A synonym for label in the form of an operator.
(<?>) :: forall s u (m :: Type -> Type) a . ParsecT s u m a -> String -> ParsecT s u m a
pandoc Text.Pandoc.Parsing
The parser p <?> msg behaves as parser p, but whenever the parser p fails without consuming any input, it replaces expect error messages with the expect error message msg. This is normally used at the end of a set alternatives where we want to return an error message in terms of a higher level construct rather than returning all possible characters. For example, if the expr parser from the try example would fail, the error message is: '...: expecting expression'. Without the (<?>) combinator, the message would be like '...: expecting "let" or letter', which is less friendly.
(<?>) :: Parser a -> String -> Parser a
snap-core Snap.Internal.Parsing
newtype (<?>) field (help :: Symbol)
optparse-generic Options.Generic
Use this to annotate a field with a type-level string (i.e. a Symbol) representing the help description for that field: 
data Example = Example
{ foo :: Int    <?> "Documentation for the foo flag"
, bar :: Double <?> "Documentation for the bar flag"
} deriving (Generic, Show)
(<?>) :: Parser a -> String -> Parser a
proto-lens Data.ProtoLens.Encoding.Bytes Data.ProtoLens.Encoding.Parser
If the parser fails, prepend an error message.
(<?>) :: ValueCodec input output -> Text -> ValueCodec input output
autodocodec Autodocodec Autodocodec.Codec
Add a comment to a codec This is an infix version of CommentCodec > (?) = flip CommentCodec
(<?>) :: Parsing m => m a -> String -> m a
Cabal-syntax Distribution.Compat.Parsing
Give a parser a name
(<?>) :: Parser x s a -> e -> Parser e s a
bytesmith Data.Bytes.Parser
Infix version of annotate.
(<?>) :: Parser a -> JSONPathElement -> Parser a
Agda Agda.Interaction.JSON
(<?>) :: Applicative m => m Doc -> m Doc -> m Doc
Agda Agda.TypeChecking.Pretty
(<?>) :: Doc -> Doc -> Doc
Agda Agda.Utils.Pretty
a ? b = hang a 2 b
(<?>) :: Prod r e t a -> e -> Prod r e t a
Earley Text.Earley Text.Earley.Grammar
A named production (used for reporting expected things).
(<?>) :: Boomerang (ParserError p) tok a b -> String -> Boomerang (ParserError p) tok a b
boomerang Text.Boomerang.Error
annotate a parse error with an additional Expect message 
satisfy isUpper <?> 'an uppercase character'
(<?>) :: (Show t, ToSQL t) => SQL -> t -> SQL
hpqtypes Database.PostgreSQL.PQTypes.SQL
Embed parameter value inside existing SQL. Example: 
f :: Int32 -> String -> SQL
f idx name = "SELECT foo FROM bar WHERE id =" <?> idx <+> "AND name =" <?> name
(<?>) :: (Text, Text) -> PU t a -> PU t a
xml-picklers Data.XML.Pickle
Override the last backtrace level in the error report.
(<?>) :: STR a -> String -> STR a
RefSerialize Data.RefSerialize.Parser
(<?>) :: Parser t e => Parser t Char -> String -> Parser t Char
hw-parser HaskellWorks.Data.Parser
(<?>) :: () => ParsecT s u m a -> String -> ParsecT s u m a
parsec-class Text.Parsec.Class
The parser p <?> msg behaves as parser p, but whenever the parser p fails without consuming any input, it replaces expect error messages with the expect error message msg. This is normally used at the end of a set alternatives where we want to return an error message in terms of a higher level construct rather than returning all possible characters. For example, if the expr parser from the try example would fail, the error message is: '...: expecting expression'. Without the (<?>) combinator, the message would be like '...: expecting "let" or letter', which is less friendly.
(<?>) :: L a -> Text -> L a
toml-reader-parse TOML.Parse, htoml-parse Data.Toml.Parse
Add textual annotation to the provided located thing. The annotation will be shows as part of error message if the location ultimately gets passed to throwParseError.
(<?>) :: Validator x inp a -> e -> Validator e inp a
valida Valida
A synonym for label with its arguments flipped.
(<?>) :: ValidationRule x a -> e -> ValidationRule e a
valida-base Valida
A synonym for label with its arguments flipped.