1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
|
{-# LANGUAGE GeneralizedNewtypeDeriving #-}
module Basement.MutableBuilder
( Builder(..)
, BuildingState(..)
) where
import Basement.Compat.Base
import Basement.Compat.MonadTrans
import Basement.Types.OffsetSize
import Basement.Monad
newtype Builder collection mutCollection step state err a = Builder
{ runBuilder :: State (Offset step, BuildingState collection mutCollection step (PrimState state), Maybe err) state a }
deriving (Functor, Applicative, Monad)
-- | The in-progress state of a building operation.
--
-- The previous buffers are in reverse order, and
-- this contains the current buffer and the state of
-- progress packing the elements inside.
data BuildingState collection mutCollection step state = BuildingState
{ prevChunks :: [collection]
, prevChunksSize :: !(CountOf step)
, curChunk :: mutCollection state
, chunkSize :: !(CountOf step)
}
instance Monad state => MonadFailure (Builder collection mutCollection step state err) where
type Failure (Builder collection mutCollection step state err) = err
mFail builderError = Builder $ State $ \(offset, bs, _) ->
return ((), (offset, bs, Just builderError))
|
