| Portability | portable |
|---|---|
| Stability | development |
| Maintainer | mariusz@scrive.com |
| Safe Haskell | None |
Text.JSON.FromJSValue
Contents
Description
Interface for extracting data from JSValue.
- class FromJSValue a where
- fromJSValue :: JSValue -> Maybe a
- fromJSValueM :: (JSValueContainer c, MonadReader c m) => m (Maybe a)
- fromJSValueField :: (JSValueContainer c, MonadReader c m, FromJSValue a) => String -> m (Maybe a)
- fromJSValueFieldBase64 :: (JSValueContainer c, MonadReader c m) => String -> m (Maybe ByteString)
- fromJSValueFieldCustom :: (JSValueContainer c, MonadReader c m) => String -> m (Maybe a) -> m (Maybe a)
- fromJSValueCustomMany :: (JSValueContainer c, MonadReader c m) => m (Maybe a) -> m (Maybe [a])
- fromJSValueCustomList :: (JSValueContainer c, MonadReader c m) => [m (Maybe a)] -> m (Maybe [a])
- withJSValue :: Monad m => JSValue -> ReaderT JSValue m a -> m a
Basic Parsing
class FromJSValue a whereSource
Structures that can be parsed from JSON. Instances must declare either fromJSValue (parse directly from JSValue) or fromJSValueM (uses MonadReader)
Methods
fromJSValue :: JSValue -> Maybe aSource
fromJSValueM :: (JSValueContainer c, MonadReader c m) => m (Maybe a)Source
Instances
| FromJSValue Bool | |
| FromJSValue Int | |
| FromJSValue Integer | |
| FromJSValue String | |
| FromJSValue ByteString | |
| FromJSValue JSValue | |
| FromJSValue a => FromJSValue [a] | |
| FromJSValue a => FromJSValue (Maybe a) | |
| (FromJSValue a, FromJSValue b) => FromJSValue (a, b) |
Data Extraction
fromJSValueField :: (JSValueContainer c, MonadReader c m, FromJSValue a) => String -> m (Maybe a)Source
Reading the value that is on some field. With field if current JSON is not object
fromJSValueFieldBase64 :: (JSValueContainer c, MonadReader c m) => String -> m (Maybe ByteString)Source
Version of fromJSValueField for Base64 encoded data to avoid memory leak.
fromJSValueFieldCustom :: (JSValueContainer c, MonadReader c m) => String -> m (Maybe a) -> m (Maybe a)Source
Generalization of fromJSValueField. Does not use FromJSValue instances
fromJSValueCustomMany :: (JSValueContainer c, MonadReader c m) => m (Maybe a) -> m (Maybe [a])Source
Runs parser on each element of underlaying json. Returns Just iff JSON is array.
fromJSValueCustomList :: (JSValueContainer c, MonadReader c m) => [m (Maybe a)] -> m (Maybe [a])Source
Generalization of fromJSValueCustomMany, where each element of array can have different parser.