git-annex/doc/bugs/Build_failing_on_Windows_since_ef3ab0769.mdwn

Due to the type change of `tryMakeLockHandle` in commit ef3ab0769, compilation of git-annex is currently failing on Windows with the below error.  I am unsure of the best way to fix it.

[[!format txt """
Utility\LockPool\Windows.hs:25:19: error:
    * Couldn't match type `(LockHandle, t1)' with `LockHandle'
      Expected type: IO (Maybe LockHandle)
        Actual type: IO (Maybe (LockHandle, t1))
    * In the expression:
        tryMakeLockHandle
          P.lockPool file (\ p f -> P.tryTakeLock p f LockShared)
          (\ f _ -> fmap mk <$> F.lockShared f)
      In an equation for `lockShared':
          lockShared file
            = tryMakeLockHandle
                P.lockPool file (\ p f -> P.tryTakeLock p f LockShared)
                (\ f _ -> fmap mk <$> F.lockShared f)
   |
25 | lockShared file = tryMakeLockHandle P.lockPool file

   |                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^...

Utility\LockPool\Windows.hs:27:18: error:
    * Couldn't match type `FileLockOps' with `(FileLockOps, t1)'
      Expected type: IO (Maybe (FileLockOps, t1))
        Actual type: IO (Maybe FileLockOps)
    * In the expression: fmap mk <$> F.lockShared f
      In the fourth argument of `tryMakeLockHandle', namely
        `(\ f _ -> fmap mk <$> F.lockShared f)'
      In the expression:
        tryMakeLockHandle
          P.lockPool file (\ p f -> P.tryTakeLock p f LockShared)
          (\ f _ -> fmap mk <$> F.lockShared f)
   |
27 |         (\f _ -> fmap mk <$> F.lockShared f)

   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^

Utility\LockPool\Windows.hs:36:22: error:
    * Couldn't match type `(LockHandle, t0)' with `LockHandle'
      Expected type: IO (Maybe LockHandle)
        Actual type: IO (Maybe (LockHandle, t0))
    * In the expression:
        tryMakeLockHandle
          P.lockPool file (\ p f -> P.tryTakeLock p f LockExclusive)
          (\ f _ -> fmap mk <$> F.lockExclusive f)
      In an equation for `lockExclusive':
          lockExclusive file
            = tryMakeLockHandle
                P.lockPool file (\ p f -> P.tryTakeLock p f LockExclusive)
                (\ f _ -> fmap mk <$> F.lockExclusive f)
   |
36 | lockExclusive file = tryMakeLockHandle P.lockPool file

   |                      ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^...

Utility\LockPool\Windows.hs:38:18: error:
    * Couldn't match type `FileLockOps' with `(FileLockOps, t0)'
      Expected type: IO (Maybe (FileLockOps, t0))
        Actual type: IO (Maybe FileLockOps)
    * In the expression: fmap mk <$> F.lockExclusive f
      In the fourth argument of `tryMakeLockHandle', namely
        `(\ f _ -> fmap mk <$> F.lockExclusive f)'
      In the expression:
        tryMakeLockHandle
          P.lockPool file (\ p f -> P.tryTakeLock p f LockExclusive)
          (\ f _ -> fmap mk <$> F.lockExclusive f)
   |
38 |         (\f _ -> fmap mk <$> F.lockExclusive f)

   |                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
"""]]

[[!meta author=jwodder]]
[[!tag projects/datalad]]

> [[fixed|done]] --[[Joey]]