To be clear : I’m annoyed with myself that this impacted a package that depends on vector, but this does seem to be the case that the newest bug fix release for vector actually revealed a broken design for the vector instances / data types in the inline-r package.
To;dr — I suggest patching inline-r to remove the s parameter in its immutable vector data types On Sat, Dec 29, 2018 at 6:48 PM Carter Schonwald <carter.schonw...@gmail.com> wrote: > so i took a look .. (also the inline-r devs seem to have done a hackage > revision so you wont hit that issue in your current setup if you do a cabal > update ..) > and it seems like the type definitions in inline-r are kinda bogus and > you should get them patched ... > > the MVector type class, and related type families, all assume your mutable > type has the last two arguments as the io/state token and then the element > type > > eg > basicLength :: v s a -> Int > <http://hackage.haskell.org/package/base-4.12.0.0/docs/Data-Int.html#t:Int> > > > i looked at > https://github.com/tweag/HaskellR/blob/1292c8a9562764d34ee4504b54d93248eb7346fe/inline-r/src/Data/Vector/SEXP.hs#L346-L374 > and > > > > as a point of grounding this chat > the injective type familly in question is defined by the follwoing > > > --#if MIN_VERSION_base(4,9,0)type family Mutable > <http://hackage.haskell.org/package/vector-0.12.0.2/docs/src/Data.Vector.Generic.Base.html#Mutable> > (v > <http://hackage.haskell.org/package/vector-0.12.0.2/docs/src/Data.Vector.Generic.Base.html#local-6989586621679032525> > :: * -> *) = (mv > <http://hackage.haskell.org/package/vector-0.12.0.2/docs/src/Data.Vector.Generic.Base.html#local-6989586621679032526> > :: * -> * -> *) | mv -> v#elsetype family Mutable (v :: * -> *) :: * -> * -> > *#endif > > anyways, it looks like the Pure / immutable vector data type in inline-r > has a spurious state token argument in its definition that shouldn't be > there, OR there need to be two "s" params in inline-r instead of the one > > heres the full code i linked to in question > > > -- | Mutable R vector. Represented in memory with the same header as > 'SEXP' > > -- nodes. The second type parameter is phantom, reflecting at the type > level the > -- tag of the vector when viewed as a 'SEXP'. The tag of the vector and the > -- representation type are related via 'ElemRep'. > data MVector s ty a = MVector > { mvectorBase :: {-# UNPACK #-} !(SEXP s ty) > , mvectorOffset :: {-# UNPACK #-} !Int32 > , mvectorLength :: {-# UNPACK #-} !Int32 > } > -- | Internal wrapper type for reflection. First type parameter is the > reified > -- type to reflect. > newtype W t ty s a = W { unW :: MVector s ty a } > instance (Reifies t (AcquireIO s), VECTOR s ty a) => G.MVector (W t ty) a > where > > data Vector s (ty :: SEXPTYPE) a = Vector > { vectorBase :: {-# UNPACK #-} !(ForeignSEXP ty) , vectorOffset :: {-# > UNPACK #-} !Int32 , vectorLength :: {-# UNPACK #-} !Int32 > } > > > type instance G.Mutable (W t ty s) = Mutable.W t ty > Anyways, the fix here is to remove the s param from the Pure version of W > and "Sexp Vector" > > > > On Sat, Dec 29, 2018 at 6:16 PM Carter Schonwald < > carter.schonw...@gmail.com> wrote: > >> were you using the same version of vector in both setups? >> >> in the most recent vector release we made mutable type family injective >> in the vector package for ghc's that support it ... >> >> On Sat, Dec 29, 2018 at 1:50 PM Dominick Samperi <djsamp...@gmail.com> >> wrote: >> >>> When I use v8.6.3 of GHC under Ubuntu to install the inline-r package >>> I get the error "Type family equation violates injectivity annotation," >>> and >>> a type variable on the LHS cannot be inferred from the RHS, due to >>> the lack of injectivity (I suppose). >>> >>> On the other hand, v8.0.2 of GHC (shipped with Haskell Platform under >>> Ubuntu) does not have this problem (it has other problems). >>> >>> Has something changed in the latest version of the compiler that might >>> cause this? Possible work-around? >>> >>> FYI, the line that triggers the error is: >>> type instance G.Mutable (W t ty s) = Mutable.W t ty >>> >>> The variable that cannot be inferred is 's'. >>> >>> Thanks, >>> Dominick >>> _______________________________________________ >>> ghc-devs mailing list >>> ghc-devs@haskell.org >>> http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs >>> >>
_______________________________________________ ghc-devs mailing list ghc-devs@haskell.org http://mail.haskell.org/cgi-bin/mailman/listinfo/ghc-devs
