ekmett/lens — pull request #426 by startling (2014-04-23 03:56:53+00:00)
Title: Fix the no instance error in C.L.I.Reflection.

This one:

````bash
~/C/S/lens> cabal repl
Preprocessing library lens-4.2...
GHCi, version 7.8.2: http://www.haskell.org/ghc/ :? for help
Loading package ghc-prim ... linking ... done.
Loading package integer-gmp ... linking ... done.
Loading package base ... linking ... done.
Loading package array-0.5.0.0 ... linking ... done.
Loading package deepseq-1.3.0.2 ... linking ... done.
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Loading arbitrary code ... running ... done.
[ 1 of 85] Compiling Data.Map.Lens ( src/Data/Map/Lens.hs, interpreted )
[ 2 of 85] Compiling Control.Lens.Internal.TH ( src/Control/Lens/Internal/TH.hs, interpreted )
[ 3 of 85] Compiling Control.Lens.Internal.TupleIxedTH ( src/Control/Lens/Internal/TupleIxedTH.hs, interpreted )
[ 4 of 85] Compiling Control.Lens.Internal.Setter ( src/Control/Lens/Internal/Setter.hs, interpreted )
[ 5 of 85] Compiling Control.Lens.Internal.Review ( src/Control/Lens/Internal/Review.hs, interpreted )
[ 6 of 85] Compiling Control.Lens.Internal.Reflection ( src/Control/Lens/Internal/Reflection.hs, interpreted )

src/Control/Lens/Internal/Reflection.hs:166:7:
No instance for (B b60) arising from the ambiguity check for ‘p’
The type variable ‘b60’ is ambiguous
When checking that ‘p’
has the inferred type ‘forall r. StablePtr r’
Probable cause: the inferred type is ambiguous
In an equation for ‘reflect’:
reflect
= r
where
r = unsafePerformIO $ const <$> deRefStablePtr p <* freeStablePtr p
s = argument r
p = intPtrToStablePtr
$ reflectByte (byte0 s) .|. (reflectByte (byte1 s) `shiftL` 8)
.|. (reflectByte (byte2 s) `shiftL` 16)
.|. (reflectByte (byte3 s) `shiftL` 24)
.|. (reflectByte (byte4 s) `shiftL` 32)
.|. (reflectByte (byte5 s) `shiftL` 40)
.|. (reflectByte (byte6 s) `shiftL` 48)
.|. (reflectByte (byte7 s) `shiftL` 56)
In the instance declaration for ‘Reifies (Stable w0 w1 a) a’
Failed, modules loaded: Control.Lens.Internal.Review, Control.Lens.Internal.Setter, Control.Lens.Internal.TH, Data.Map.Lens, Control.Lens.Internal.TupleIxedTH.
*Control.Lens.Internal.Review>
````
Not sure why it's only shows up there?