Database.Relational.Query.Monad.Trans.Assigning

This module defines monad transformer which lift from context into context with assigning.

Transformer into context with assignments

data Assignings r m a

Type to accumulate assigning context. Type r is table record type.

Instances

MonadQualify q m => MonadQualify q (Assignings r m)

MonadQualify with assigning.

MonadRestrict c m => MonadRestrict c (Assignings r m)

MonadRestrict with assigning.

MonadTrans (Assignings r)

Monad m => Monad (Assignings r m)

Functor m => Functor (Assignings r m)

Applicative m => Applicative (Assignings r m)

assignings :: Monad m => m a -> Assignings r m a

Lift to Assignings

API of context with assignments

assignTo :: Monad m => Projection Flat v -> AssignTarget r v -> Assignings r m ()

Add an assignment.

(<-#) :: Monad m => AssignTarget r v -> Projection Flat v -> Assignings r m () infix 4

Add and assginment.

type AssignTarget r v = Pi r v

Target of assignment.

Result SQL set clause

extractAssignments :: (Monad m, Functor m) => Assignings r m a -> m (a, Table r -> Assignments)

Run Assignings to get Assignments