Minor simplifications and documentation fix

clash-protocols/src/Protocols/Df.hs

@@ -180,7 +180,7 @@ forceResetSanity = forceResetSanityGeneric
 
 -- | Coerce the payload of a Df stream.
 coerce :: (Coerce.Coercible a b) => Circuit (Df dom a) (Df dom b)
-coerce = fromSignals $ \(fwdA, bwdB) -> (Coerce.coerce bwdB, Coerce.coerce fwdA)
+coerce = fromSignals $ \(fwdA, bwdB) -> (bwdB, Coerce.coerce fwdA)
 
 {- | Takes one or more values from the left and "compresses" it into a single
 value that is occasionally sent to the right. Useful for taking small high-speed
@@ -335,7 +335,7 @@ pure a = Circuit (P.const ((), P.pure (Just a)))
 consume :: (C.HiddenReset dom) => Circuit (Df dom a) ()
 consume = Circuit (P.const (P.pure (Ack True), ()))
 
--- | Never acknowledge values.
+-- | Acknowledge but ignore values when out of reset, otherwise give backpressure.
 void :: (C.HiddenReset dom) => Circuit (Df dom a) ()
 void =
   Circuit
@@ -677,10 +677,10 @@ faninS ::
   Circuit (C.Vec n (Df dom a)) (Df dom a)
 faninS fS = bundleVec |> mapS (C.fold @(n C.- 1) <$> fS)
 
--- | Merge data of multiple 'Df' streams using Monoid's '<>'.
+-- | Merge data of multiple 'Df' streams using Semigroup's '<>'.
 mfanin ::
   forall n dom a.
-  (C.KnownNat n, Monoid a, 1 <= n) =>
+  (C.KnownNat n, Semigroup a, 1 <= n) =>
   Circuit (C.Vec n (Df dom a)) (Df dom a)
 mfanin = fanin (<>)
 

clash-protocols/src/Protocols/DfConv.hs

@@ -857,7 +857,7 @@ pure df a =
   Df.pure a
     |> dfToDfConvOtp df
 
--- | Ignore incoming data
+-- | Acknowledge but ignore values when out of reset, otherwise give backpressure.
 void ::
   ( DfConv df
   , HiddenClockResetEnable (Dom df)
@@ -1245,7 +1245,7 @@ fanin dfA dfB f =
       )
     |> toDfCircuit dfB
 
--- | Merge data of multiple streams using Monoid's '<>'.
+-- | Merge data of multiple streams using Semigroup's '<>'.
 mfanin ::
   ( DfConv dfA
   , DfConv dfB
@@ -1254,7 +1254,7 @@ mfanin ::
   , HiddenClockResetEnable (Dom dfA)
   , FwdPayload dfA ~ FwdPayload dfB
   , NFDataX (FwdPayload dfA)
-  , Monoid (FwdPayload dfA)
+  , Semigroup (FwdPayload dfA)
   , KnownNat numA
   , numA ~ (decNumA + 1)
   ) =>

clash-protocols/tests/Tests/Protocols/Axi4.hs

@@ -12,6 +12,7 @@ import Clash.Prelude qualified as C
 import Data.Proxy (Proxy (..))
 
 -- hedgehog
+import Clash.Hedgehog.Sized.Vector (genVec)
 import Hedgehog
 import Hedgehog.Gen qualified as Gen
 import Hedgehog.Range qualified as Range

clash-protocols/tests/Tests/Protocols/Df.hs

@@ -40,6 +40,7 @@ import Control.DeepSeq (NFData)
 import Data.Hashable (Hashable)
 
 -- hedgehog
+import Clash.Hedgehog.Sized.Vector (genVec)
 import Hedgehog
 import Hedgehog.Gen qualified as Gen
 import Hedgehog.Range qualified as Range

clash-protocols/tests/Util.hs

@@ -12,26 +12,18 @@ import Data.HashMap.Strict qualified as HashMap
 import Data.Hashable (Hashable)
 
 -- clash-prelude
-
-import Clash.Prelude (type (<=))
 import Clash.Prelude qualified as C
 
 -- extra
 import "extra" Data.List.Extra (transpose)
 import "extra" Data.List.Extra qualified as Extra
 
--- hedgehog
-import Hedgehog qualified as H
-
 chunksOf :: forall n. (C.KnownNat n) => [Int] -> C.Vec n [Int]
 chunksOf xs = vecFromList (transpose (Extra.chunksOf (C.natToNum @n) xs))
 
 vecFromList :: forall n a. (C.KnownNat n, Monoid a) => [a] -> C.Vec n a
 vecFromList as = C.takeI (unsafeCoerce (as <> repeat mempty))
 
-genVec :: (C.KnownNat n, 1 <= n) => H.Gen a -> H.Gen (C.Vec n a)
-genVec gen = sequence (C.repeat gen)
-
 -- | Count the number of times an element occurs in a list
 tally :: (Hashable a, Eq a) => [a] -> HashMap a Int
 tally = tallyOn id (const 1)