Fixes for latest GHC.

.gitignore

@@ -0,0 +1,2 @@
+.stack-work/
+dist/

Control/Monad/Exception/Base.hs

@@ -9,8 +9,12 @@ module Control.Monad.Exception.Base where
 
 import Control.Applicative
 import Control.Arrow
+import Control.Monad
 import Control.Monad.Base
 import Control.Monad.Exception.Catch
+#if MIN_VERSION_base(4,9,0) && !MIN_VERSION_base(4,13,0)
+import qualified Control.Monad.Fail as Fail
+#endif
 import Control.Monad.Loc
 import Control.Monad.Trans.Class
 import Control.Monad.Trans.Control
@@ -62,18 +66,33 @@ instance Monad m => Functor (EMT l m) where
 instance Monad m => Monad (EMT l m) where
   return = EMT . return . Right
 
-  fail s = EMT $ return $ Left ([], CheckedException $ toException $ FailException s)
-
   emt >>= f = EMT $ do
                 v <- unEMT emt
                 case v of
                   Left e  -> return (Left e)
                   Right x -> unEMT (f x)
 
+#if !MIN_VERSION_base(4,13,0)
+#if MIN_VERSION_base(4,9,0)
+  fail = Fail.fail
+#else
+  fail s = EMT $ return $ Left ([], CheckedException $ toException $ FailException s)
+#endif
+#endif
+
 instance Monad m => Applicative (EMT l m) where
   pure  = return
   (<*>) = ap
 
+#if MIN_VERSION_base(4,9,0)
+#if MIN_VERSION_base(4,13,0)
+instance Monad m => MonadFail (EMT l m) where
+#else
+instance Monad m => Fail.MonadFail (EMT l m) where
+#endif
+  fail s = EMT $ return $ Left ([], CheckedException $ toException $ FailException s)
+#endif
+
 instance (Exception e, Throws e l, Monad m) => Failure e (EMT l m) where
   failure = throw
 
@@ -96,14 +115,28 @@ instance MonadBase b m => MonadBase b (EMT l m) where
     liftBase = liftBaseDefault
 
 instance MonadBaseControl b m => MonadBaseControl b (EMT l m) where
+#if MIN_VERSION_monad_control(1,0,0)
+     type StM (EMT l m) a = ComposeSt (EMT l) m a
+     liftBaseWith = defaultLiftBaseWith
+     restoreM     = defaultRestoreM
+#else
      newtype StM (EMT l m) a = StmEMT {unStmEMT :: ComposeSt (EMT l) m a}
      liftBaseWith = defaultLiftBaseWith StmEMT
      restoreM     = defaultRestoreM   unStmEMT
+#endif
+
+-- newtype EMT l m a = EMT {unEMT :: m (Either (CallTrace, CheckedException l) a)}
 
 instance MonadTransControl (EMT l) where
+#if MIN_VERSION_monad_control(1,0,0)
+     type StT (EMT l) a = Either (CallTrace, CheckedException l) a
+     liftWith f = EMT $ fmap return $ f $ unEMT
+     restoreT   = EMT
+#else
      newtype StT (EMT l) a = StEMT {unStEMT :: Either (CallTrace, CheckedException l) a}
      liftWith f = EMT $ liftM return $ f $ liftM StEMT . unEMT
-     restoreT       = EMT . liftM unStEMT
+     restoreT   = EMT . liftM unStEMT
+#endif
 
 instance Monad m => MonadLoc (EMT l m) where
     withLoc loc (EMT emt) = EMT $ do

Control/Monad/Exception/Pure.hs

@@ -74,7 +74,10 @@ module Control.Monad.Exception.Pure (
     FailException(..), MonadZeroException(..), mplusDefault,
 
 -- * Reexports
-    Exception(..), SomeException(..), Typeable1,
+    Exception(..), SomeException(..),
+#if !MIN_VERSION_base(4,7,0)
+    Typeable1,
+#endif
     Failure(..),
 #if !MIN_VERSION_failure(0,2,0)
     Try(..), NothingException(..),

stack.yaml

@@ -0,0 +1,74 @@
+# This file was automatically generated by 'stack init'
+#
+# Some commonly used options have been documented as comments in this file.
+# For advanced use and comprehensive documentation of the format, please see:
+# https://docs.haskellstack.org/en/stable/yaml_configuration/
+
+# A warning or info to be displayed to the user on config load.
+user-message: |
+  Warning (added by new or init): Some packages were found to be incompatible with the resolver and have been left commented out in the packages section.
+  You can omit this message by removing it from stack.yaml
+
+# Resolver to choose a 'specific' stackage snapshot or a compiler version.
+# A snapshot resolver dictates the compiler version and the set of packages
+# to be used for project dependencies. For example:
+#
+# resolver: lts-3.5
+# resolver: nightly-2015-09-21
+# resolver: ghc-7.10.2
+#
+# The location of a snapshot can be provided as a file or url. Stack assumes
+# a snapshot provided as a file might change, whereas a url resource does not.
+#
+# resolver: ./custom-snapshot.yaml
+# resolver: https://example.com/snapshots/2018-01-01.yaml
+resolver: nightly-2020-06-29
+
+# User packages to be built.
+# Various formats can be used as shown in the example below.
+#
+# packages:
+# - some-directory
+# - https://example.com/foo/bar/baz-0.0.2.tar.gz
+#   subdirs:
+#   - auto-update
+#   - wai
+packages:
+- .
+
+# Dependency packages to be pulled from upstream that are not in the resolver.
+# These entries can reference officially published versions as well as
+# forks / in-progress versions pinned to a git hash. For example:
+#
+# extra-deps:
+# - acme-missiles-0.3
+# - git: https://github.com/commercialhaskell/stack.git
+#   commit: e7b331f14bcffb8367cd58fbfc8b40ec7642100a
+#
+extra-deps:
+- failure-0.2.0.3
+- monadloc-0.7.1
+
+# Override default flag values for local packages and extra-deps
+# flags: {}
+
+# Extra package databases containing global packages
+# extra-package-dbs: []
+
+# Control whether we use the GHC we find on the path
+# system-ghc: true
+#
+# Require a specific version of stack, using version ranges
+# require-stack-version: -any # Default
+# require-stack-version: ">=2.3"
+#
+# Override the architecture used by stack, especially useful on Windows
+# arch: i386
+# arch: x86_64
+#
+# Extra directories used by stack for building
+# extra-include-dirs: [/path/to/dir]
+# extra-lib-dirs: [/path/to/dir]
+#
+# Allow a newer minor version of GHC than the snapshot specifies
+# compiler-check: newer-minor