From 689998a77dc948e95313db47807cddd12cdb9118 Mon Sep 17 00:00:00 2001
From: Sandy Maguire <sandy@sandymaguire.me>
Date: Sat, 20 Apr 2019 06:00:55 -0400
Subject: [PATCH] Prefer interpret over reinterpret for effect transformers

---
 ChangeLog.md           | 4 ++++
 src/Polysemy/Reader.hs | 4 ++--
 src/Polysemy/Trace.hs  | 7 +++++--
 src/Polysemy/Writer.hs | 4 ++--
 4 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/ChangeLog.md b/ChangeLog.md
index b77bb65..b9ffd5e 100644
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -11,3 +11,7 @@
 - Initial release
 
 ## Unreleased changes
+
+- `runInputAsReader`, `runTraceAsOutput` and `runOutputAsWriter` have more
+    generalized types
+- Aded `runStateInIO`
diff --git a/src/Polysemy/Reader.hs b/src/Polysemy/Reader.hs
index 4282628..e63d262 100644
--- a/src/Polysemy/Reader.hs
+++ b/src/Polysemy/Reader.hs
@@ -49,8 +49,8 @@ runReader_b = runReader
 
 ------------------------------------------------------------------------------
 -- | Transform an 'Input' effect into a 'Reader' effect.
-runInputAsReader :: Sem (Input i ': r) a -> Sem (Reader i ': r) a
-runInputAsReader = reinterpret $ \case
+runInputAsReader :: Member (Reader i) r => Sem (Input i ': r) a -> Sem r a
+runInputAsReader = interpret $ \case
   Input -> ask
 {-# INLINE runInputAsReader #-}
 
diff --git a/src/Polysemy/Trace.hs b/src/Polysemy/Trace.hs
index b16e76d..8ffdbb5 100644
--- a/src/Polysemy/Trace.hs
+++ b/src/Polysemy/Trace.hs
@@ -43,8 +43,11 @@ runIgnoringTrace = interpret $ \case
 
 ------------------------------------------------------------------------------
 -- | Transform a 'Trace' effect into a 'Output' 'String' effect.
-runTraceAsOutput :: Sem (Trace ': r) a -> Sem (Output String ': r) a
-runTraceAsOutput = reinterpret $ \case
+runTraceAsOutput
+    :: Member (Output String) r
+    => Sem (Trace ': r) a
+    -> Sem r a
+runTraceAsOutput = interpret $ \case
   Trace m -> output m
 {-# INLINE runTraceAsOutput #-}
 
diff --git a/src/Polysemy/Writer.hs b/src/Polysemy/Writer.hs
index 47135ff..87f41ad 100644
--- a/src/Polysemy/Writer.hs
+++ b/src/Polysemy/Writer.hs
@@ -32,8 +32,8 @@ makeSem ''Writer
 
 ------------------------------------------------------------------------------
 -- | Transform an 'Output' effect into a 'Writer' effect.
-runOutputAsWriter :: Sem (Output o ': r) a -> Sem (Writer o ': r) a
-runOutputAsWriter = reinterpret \case
+runOutputAsWriter :: Member (Writer o) r => Sem (Output o ': r) a -> Sem r a
+runOutputAsWriter = interpret \case
   Output o -> tell o
 {-# INLINE runOutputAsWriter #-}