From 7b38a7644e5659cb31aa469b7d070610f1365488 Mon Sep 17 00:00:00 2001
From: Janus Troelsen <janus@flipstone.com>
Date: Fri, 23 Oct 2026 23:05:43 -0600
Subject: [PATCH] Do not depend on Monad(return)

This still retains use of the `return` binding, but according to the
reduced breakage plan, the binding will stay, as a function outside of
the class. So we just need to import it as part of explicit import
lists.

See
https://gitlab.haskell.org/ghc/ghc/-/wikis/Proposal/Monad-Of-No-Return#reduced-breakage-variant
---
 happstack-server.cabal                  | 4 ++--
 src/Happstack/Server/Internal/Monads.hs | 8 +++-----
 src/Happstack/Server/RqData.hs          | 2 +-
 3 files changed, 6 insertions(+), 8 deletions(-)

diff --git a/happstack-server.cabal b/happstack-server.cabal
index 7ec4189..4f3784a 100644
--- a/happstack-server.cabal
+++ b/happstack-server.cabal
@@ -81,7 +81,7 @@ Library
                        network-uri >= 2.6 && < 2.7
   else
      build-depends:    network               < 2.6
-  Build-Depends:       base                   >= 4    && < 5,
+  Build-Depends:       base                   >= 4.8  && < 5,
                        base64-bytestring      >= 1.0  && < 1.3,
                        blaze-html             >= 0.5  && < 0.10,
                        bytestring,
@@ -138,7 +138,7 @@ Test-Suite happstack-server-tests
   GHC-Options: -threaded
   hs-source-dirs: tests
   Build-depends: HUnit,
-                 base >= 4    && < 5,
+                 base >= 4.8  && < 5,
                  bytestring,
                  containers,
                  happstack-server,
diff --git a/src/Happstack/Server/Internal/Monads.hs b/src/Happstack/Server/Internal/Monads.hs
index 3505a55..19474d2 100644
--- a/src/Happstack/Server/Internal/Monads.hs
+++ b/src/Happstack/Server/Internal/Monads.hs
@@ -61,7 +61,7 @@ import Happstack.Server.Internal.RFC822Headers   (parseContentType)
 import Happstack.Server.Internal.Types           (EscapeHTTP(..), canHaveBody)
 import Happstack.Server.Internal.TimeoutIO       (TimeoutIO)
 import Happstack.Server.Types
-import Prelude                                   (Bool(..), Either(..), Eq(..), Functor(..), IO, Monad(..), Char, Maybe(..), String, Show(..), ($), (.), (>), (++), (&&), (||), (=<<), const, concatMap, flip, id, otherwise, zip)
+import Prelude                                   (Bool(..), Either(..), Eq(..), Functor(..), IO, Monad(..), return, (>>), Char, Maybe(..), String, Show(..), ($), (.), (>), (++), (&&), (||), (=<<), const, concatMap, flip, id, otherwise, zip)
 
 -- | An alias for 'WebT' when using 'IO'.
 type Web a = WebT IO a
@@ -194,7 +194,7 @@ instance (Monad m, MonadPlus m) => Monoid (ServerPartT m a) where
     mappend = (SG.<>)
 
 instance (Monad m, Functor m) => Applicative (ServerPartT m) where
-    pure = return
+    pure a = ServerPartT $ pure a
     (<*>) = ap
 
 instance (Functor m, MonadPlus m) => Alternative (ServerPartT m) where
@@ -477,8 +477,6 @@ type UnWebT m a = m (Maybe (Either Response a, FilterFun Response))
 instance Monad m => Monad (WebT m) where
     m >>= f = WebT $ unWebT m >>= unWebT . f
     {-# INLINE (>>=) #-}
-    return a = WebT $ return a
-    {-# INLINE return #-}
 
 #if MIN_VERSION_base(4,9,0)
 instance MonadFail m => MonadFail (WebT m) where
@@ -567,7 +565,7 @@ localContext fn hs
     = withRequest $ \rq -> fn (runServerPartT hs rq)
 
 instance (Monad m, Functor m) => Applicative (WebT m) where
-    pure = return
+    pure a = WebT $ pure a
     (<*>) = ap
 
 instance (Functor m, MonadPlus m) => Alternative (WebT m) where
diff --git a/src/Happstack/Server/RqData.hs b/src/Happstack/Server/RqData.hs
index 17ad891..50f71a3 100644
--- a/src/Happstack/Server/RqData.hs
+++ b/src/Happstack/Server/RqData.hs
@@ -114,7 +114,7 @@ instance (Monoid e) => Applicative (ReaderError r e) where
 #else
 instance (Monoid e, DeprecatedError.Error e) => Applicative (ReaderError r e) where
 #endif
-    pure = return
+    pure a = ReaderError $ pure a
     (ReaderError (ReaderT f)) <*> (ReaderError (ReaderT a))
         = ReaderError $ ReaderT $ \env -> (f env) `apEither` (a env)