Backport List to Data.List.Compat

Addresses one check box in #24.
haskell-compat · Apr 23, 2024 · a77a453 · a77a453
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diff --git a/base-compat/CHANGES.markdown b/base-compat/CHANGES.markdown
@@ -1,6 +1,7 @@
 ## Changes in 0.14.0 [????.??.??]
  - Sync with `base-4.20`/GHC 9.10
  - Backport `foldl'` to `Prelude.Compat`
+ - Backport `List` to `Data.List.Compat` (when building with GHC 9.6 or later)
 
 ## Changes in 0.13.1 [2023.10.11]
  - Sync with `base-4.19`/GHC 9.8

diff --git a/base-compat/README.markdown b/base-compat/README.markdown
@@ -166,6 +166,7 @@ So far the following is covered.
  * `heqT` to `Data.Typeable.Compat`
  * `unzip` to `Data.Functor.Compat`
  * `(!?)` and `unsnoc` to `Data.List.Compat`
+ * `List` to `Data.List.Compat` (when building with GHC 9.6 or later)
  * `getSolo` to `Data.Tuple.Compat`
  * `decT` and `hdecT` to `Data.Typeable.Compat`
  * `decTypeRep` to `Type.Reflection.Compat`

diff --git a/base-compat/src/Data/List/Compat.hs b/base-compat/src/Data/List/Compat.hs
@@ -5,6 +5,11 @@
 #endif
 module Data.List.Compat (
   module Base
+
+#if MIN_VERSION_base(4,18,0) && !(MIN_VERSION_base(4,20,0))
+, List
+#endif
+
 #if !(MIN_VERSION_base(4,19,0))
 , (!?)
 , unsnoc
@@ -105,6 +110,10 @@ import GHC.Exts (build)
 import Prelude.Compat hiding (foldr, null)
 #endif
 
+#if MIN_VERSION_base(4,18,0) && !(MIN_VERSION_base(4,20,0))
+import GHC.List (List)
+#endif
+
 #if !(MIN_VERSION_base(4,5,0))
 -- | The 'dropWhileEnd' function drops the largest suffix of a list
 -- in which the given predicate holds for all elements.  For example: