Compatibility with GHC 8.10 and template-haskell 2.16.

Taken from 
https://raw.githubusercontent.com/archlinux/svntogit-community/packages/haskell-language-haskell-extract/trunk/ghc-8.10.patch

diff --git a/src/Language/Haskell/Extract.hs b/src/Language/Haskell/Extract.hs
index 3e8958b..43dfe04 100644
--- a/src/Language/Haskell/Extract.hs
+++ b/src/Language/Haskell/Extract.hs
@@ -1,3 +1,4 @@
+{-# LANGUAGE CPP #-}
 module Language.Haskell.Extract (
   functionExtractor,
   functionExtractorMap,
@@ -25,7 +26,11 @@ extractAllFunctions pattern =
 functionExtractor :: String -> ExpQ
 functionExtractor pattern =
   do functions <- extractAllFunctions pattern
-     let makePair n = TupE [ LitE $ StringL n , VarE $ mkName n]
+     let makePair n = TupE
+#if MIN_VERSION_template_haskell(2,16,0)
+                           $ map Just
+#endif
+                           [ LitE $ StringL n , VarE $ mkName n]
      return $ ListE $ map makePair functions
 
 
t'></td></tr></table>
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<tr><td><span title='2020-05-20 08:30:35 -0400'>2020-05-20</span></td><td><a href='/guix/commit/gnu/bootloader/depthcharge.scm?id=b460ba7992a0b4af2ddb5927dcf062784539ef7b'>bootloader: grub: Allow booting from a Btrfs subvolume.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/bootloader/grub.scm (strip-mount-point): Remove procedure.
(normalize-file): Add procedure.
(grub-configuration-file): New BTRFS-SUBVOLUME-FILE-NAME parameter.  When
defined, prepend its value to the kernel and initrd file names, using the
NORMALIZE-FILE procedure.  Adjust the call to EYE-CANDY to pass the
BTRFS-SUBVOLUME-FILE-NAME argument.  Normalize the KEYMAP file as well.
(eye-candy): Add a BTRFS-SUBVOLUME-FILE-NAME parameter, and use it, along with
the NORMALIZE-FILE procedure, to normalize the FONT-FILE and IMAGE nested
variables.  Adjust doc.
* gnu/bootloader/depthcharge.scm (depthcharge-configuration-file): Adapt.
* gnu/bootloader/extlinux.scm (extlinux-configuration-file): Likewise.
* gnu/system/file-systems.scm (btrfs-subvolume?)
(btrfs-store-subvolume-file-name): New procedures.
* gnu/system.scm (operating-system-bootcfg): Specify the Btrfs
subvolume file name the store resides on to the
`operating-system-bootcfg' procedure, using the new
BTRFS-SUBVOLUME-FILE-NAME argument.
* doc/guix.texi (File Systems): Add a Btrfs subsection to document the use of
subvolumes.
* gnu/tests/install.scm (%btrfs-root-on-subvolume-os)
(%btrfs-root-on-subvolume-os-source)
(%btrfs-root-on-subvolume-installation-script)
(%test-btrfs-root-on-subvolume-os): New variables.
</span></span></td><td>Maxim Cournoyer</td></tr>
<tr><td><span title='2019-04-03 18:21:42 +0200'>2019-04-03</span></td><td><a href='/guix/commit/gnu/bootloader/depthcharge.scm?id=96c90474c0cbfe88d1dccb9cb52a0f1b3a1505e7'>gnu: Add configuration for depthcharge bootloader.</a><span class='msg-avail'>...<span class='msg-tooltip'>* gnu/bootloader/depthcharge: New file.
* gnu/local.mk [GNU_SYSTEM_MODULES]: Adjust accordingly.

Signed-off-by: Ludovic Courtès &lt;ludo@gnu.org&gt;
</span></span></td><td>Timothy Sample</td></tr>