102 lines
2.6 KiB
Idris
102 lines
2.6 KiB
Idris
module Quox.EffExtra
|
|
|
|
import public Control.Eff
|
|
|
|
import Data.IORef
|
|
|
|
|
|
export
|
|
localAt : (0 lbl : tag) -> Has (StateL lbl s) fs =>
|
|
(s -> s) -> Eff fs a -> Eff fs a
|
|
localAt lbl f act = do
|
|
old <- getAt lbl
|
|
modifyAt lbl f *> act <* putAt lbl old
|
|
|
|
export %inline
|
|
localAt_ : (0 lbl : tag) -> Has (StateL lbl s) fs =>
|
|
s -> Eff fs a -> Eff fs a
|
|
localAt_ lbl x = localAt lbl $ const x
|
|
|
|
export %inline
|
|
local : Has (State s) fs => (s -> s) -> Eff fs a -> Eff fs a
|
|
local = localAt ()
|
|
|
|
export %inline
|
|
local_ : Has (State s) fs => s -> Eff fs a -> Eff fs a
|
|
local_ = localAt_ ()
|
|
|
|
|
|
export
|
|
hasDrop : (0 neq : Not (a = b)) ->
|
|
(ha : Has a fs) => (hb : Has b fs) =>
|
|
Has a (drop fs hb)
|
|
hasDrop neq {ha = Z} {hb = Z} = void $ neq Refl
|
|
hasDrop neq {ha = S ha} {hb = Z} = ha
|
|
hasDrop neq {ha = Z} {hb = S hb} = Z
|
|
hasDrop neq {ha = S ha} {hb = S hb} = S $ hasDrop neq {ha, hb}
|
|
|
|
private
|
|
0 ioNotState : Not (IO = StateL _ _)
|
|
ioNotState Refl impossible
|
|
|
|
export
|
|
runStateIORefAt : (0 lbl : tag) -> (Has IO fs, Has (StateL lbl s) fs) =>
|
|
IORef s -> Eff fs a -> Eff (fs - StateL lbl s) a
|
|
runStateIORefAt lbl ref act = do
|
|
let hh : Has IO (fs - StateL lbl s) := hasDrop ioNotState
|
|
(val, st) <- runStateAt lbl !(readIORef ref) act
|
|
writeIORef ref st $> val
|
|
|
|
export %inline
|
|
runStateIORef : (Has IO fs, Has (State s) fs) =>
|
|
IORef s -> Eff fs a -> Eff (fs - State s) a
|
|
runStateIORef = runStateIORefAt ()
|
|
|
|
|
|
export %inline
|
|
evalStateAt : (0 lbl : tag) -> Has (StateL lbl s) fs =>
|
|
s -> Eff fs a -> Eff (fs - StateL lbl s) a
|
|
evalStateAt lbl s act = map fst $ runStateAt lbl s act
|
|
|
|
export %inline
|
|
evalState : Has (State s) fs => s -> Eff fs a -> Eff (fs - State s) a
|
|
evalState = evalStateAt ()
|
|
|
|
|
|
|
|
public export
|
|
data Length : List a -> Type where
|
|
Z : Length []
|
|
S : Length xs -> Length (x :: xs)
|
|
|
|
export
|
|
subsetWith : Length xs => (forall z. Has z xs -> Has z ys) ->
|
|
Subset xs ys
|
|
subsetWith @{Z} f = []
|
|
subsetWith @{S len} f = f Z :: subsetWith (f . S)
|
|
|
|
export
|
|
subsetSelf : Length xs => Subset xs xs
|
|
subsetSelf = subsetWith id
|
|
|
|
export
|
|
subsetTail : Length xs => Subset xs (x :: xs)
|
|
subsetTail = subsetWith S
|
|
|
|
|
|
-- [fixme] allow the error to be anywhere in the effect list
|
|
export
|
|
wrapErrAt : Length fs => (0 lbl : tag) -> (e -> e) ->
|
|
Eff (ExceptL lbl e :: fs) a -> Eff (ExceptL lbl e :: fs) a
|
|
wrapErrAt lbl f act =
|
|
rethrowAt lbl . mapFst f =<< lift @{subsetTail} (runExceptAt lbl act)
|
|
|
|
export %inline
|
|
wrapErr : Length fs => (e -> e) ->
|
|
Eff (Except e :: fs) a -> Eff (Except e :: fs) a
|
|
wrapErr = wrapErrAt ()
|
|
|
|
|
|
export %inline
|
|
runIO : (MonadRec io, HasIO io) => Eff [IO] a -> io a
|
|
runIO act = runEff act [liftIO]
|