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  1. cmap :: forall a b (m :: Type -> Type) . (a -> b) -> LogAction m b -> LogAction m a

    co-log-core Colog.Core.Action

    This combinator is contramap from contravariant functor. It is useful when you have something like 

    data LogRecord = LR
{ lrName    :: LoggerName
, lrMessage :: Text
}
    and you need to provide LogAction which consumes LogRecord 
    logRecordAction :: LogAction m LogRecord
    when you only have action that consumes Text 
    logTextAction :: LogAction m Text
    With cmap you can do the following: 
    logRecordAction :: LogAction m LogRecord
logRecordAction = cmap lrMesssage logTextAction
    This action will print only lrMessage from LogRecord. But if you have formatting function like this: 
    formatLogRecord :: LogRecord -> Text
    you can apply it instead of lrMessage to log formatted LogRecord as Text.

  2. cmapM :: Monad m => (a -> m b) -> LogAction m b -> LogAction m a

    co-log-core Colog.Core.Action

    cmapM combinator is similar to cmap but allows to call monadic functions (functions that require extra context) to extend consumed value. Consider the following example. You have this logging record: 

    data LogRecord = LR
{ lrTime    :: UTCTime
, lrMessage :: Text
}
    and you also have logging consumer inside IO for such record: 
    logRecordAction :: LogAction IO LogRecord
    But you need to return consumer only for Text messages: 
    logTextAction :: LogAction IO Text
    If you have function that can extend Text to LogRecord like the function below: 
    withTime :: Text -> IO LogRecord
withTime msg = do
time <- getCurrentTime
pure (LR time msg)
    you can achieve desired behavior with cmapM in the following way: 
    logTextAction :: LogAction IO Text
logTextAction = cmapM withTime myAction

  3. cmapMaybe :: forall (m :: Type -> Type) a b . Applicative m => (a -> Maybe b) -> LogAction m b -> LogAction m a

    co-log-core Colog.Core.Action

    cmap for convertions that may fail

  4. cmapMaybeM :: Monad m => (a -> m (Maybe b)) -> LogAction m b -> LogAction m a

    co-log-core Colog.Core.Action

    Similar to cmapMaybe but for convertions that may fail inside a monadic context.

  5. type HasLinearMap (v :: Type -> Type) = (HasBasis v, Traversable v)

    diagrams-core Diagrams.Core

    HasLinearMap is a constraint synonym, just to help shorten some of the ridiculously long constraint sets.

  6. newtype SubMap b (v :: Type -> Type) n m

    diagrams-core Diagrams.Core

    A SubMap is a map associating names to subdiagrams. There can be multiple associations for any given name.

  7. SubMap :: Map Name [Subdiagram b v n m] -> SubMap b (v :: Type -> Type) n m

    diagrams-core Diagrams.Core

    No documentation available.

  8. subMap :: forall (v :: Type -> Type) m n b . (Metric v, Semigroup m, OrderedField n) => Lens' (QDiagram b v n m) (SubMap b v n m)

    diagrams-core Diagrams.Core

    Lens onto the SubMap of a QDiagram (i.e. an association from names to subdiagrams).

  9. type HasLinearMap (v :: Type -> Type) = (HasBasis v, Traversable v)

    diagrams-core Diagrams.Core.Transform

    HasLinearMap is a constraint synonym, just to help shorten some of the ridiculously long constraint sets.

  10. newtype SubMap b (v :: Type -> Type) n m

    diagrams-core Diagrams.Core.Types

    A SubMap is a map associating names to subdiagrams. There can be multiple associations for any given name.

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