Drop support for 7.4.x so we can use InstanceSigs to deal with Functor not being a super class of Monad on older GHC

Author: dagit

.github/workflows/ci.yml

@@ -68,8 +68,6 @@ jobs:
             allow-failure: false
           - ghc: 7.6.3
             allow-failure: false
-          - ghc: 7.4.2
-            allow-failure: false
       fail-fast: false
     steps:
       - name: apt

logict-sequence.cabal

@@ -29,7 +29,7 @@ extra-source-files: CHANGELOG.md
                     README.md
                     include/logict-sequence.h
 
-tested-with: GHC ==7.4.2 GHC ==7.6.3 GHC ==7.8.4 GHC ==7.10.3 GHC ==8.0.2 GHC ==8.2.2 GHC ==8.4.4 GHC ==8.6.5 GHC ==8.8.4 GHC ==8.10.4
+tested-with: GHC ==7.6.3 GHC ==7.8.4 GHC ==7.10.3 GHC ==8.0.2 GHC ==8.2.2 GHC ==8.4.4 GHC ==8.6.5 GHC ==8.8.4 GHC ==8.10.4
 
 
 source-repository head
@@ -47,7 +47,7 @@ library
 
     -- LANGUAGE extensions used by modules in this package.
     -- other-extensions:
-    build-depends: base >=4.5 && <5
+    build-depends: base >=4.6 && <5
     build-depends: mtl >=2.0 && <2.3
     build-depends: type-aligned >= 0.9.6 && < 0.10
     build-depends: sequence >= 0.9.8 && < 0.10
@@ -71,7 +71,7 @@ test-suite logict-test
   hs-source-dirs:   test
   default-language: Haskell2010
   main-is:          Test.hs
-  build-depends:    base >=4.5 && < 5
+  build-depends:    base >=4.6 && < 5
                   , logict-sequence
                   , hedgehog
                   , hspec

src/Control/Monad/Logic/Sequence/Internal.hs

@@ -9,6 +9,7 @@
 {-# LANGUAGE DeriveGeneric #-}
 {-# LANGUAGE DeriveFunctor #-}
 {-# LANGUAGE ScopedTypeVariables #-}
+{-# LANGUAGE InstanceSigs #-}
 
 #ifdef USE_PATTERN_SYNONYMS
 {-# LANGUAGE PatternSynonyms #-}
@@ -329,6 +330,7 @@ instance (Functor m, Monad m) => Monoid (SeqT m a) where
 
 instance MonadTrans SeqT where
   {-# INLINE lift #-}
+  lift :: (Functor m, Monad m) => m a -> SeqT m a
   lift m = fromView (m >>= single)
 
 instance (Functor m, Monad m) => MonadLogic (SeqT m) where