Haskell - can't find package

haskell package cabal cabal-install
Drew picture Drew · Dec 10, 2012 · Viewed 12.5k times · Source

I have a package installed via cabal: Data.Vector

But when I attempt to compile a program that has import Data.Vector in it:

Drews-MacBook-Pro:Blokus-AI drewgross$ ghc --make -O2 -prof -auto-all playGame

Grid.hs:28:8:
    Could not find module `Data.Vector'
    Perhaps you meant
      Data.Tensor (from Tensor-1.0.0.1)
      Data.Functor (from base)
    Use -v to see a list of the files searched for.
Drews-MacBook-Pro:Blokus-AI drewgross$

The command I used to install was:

cabal install -p --reinstall --force-reinstalls vector

I've done other various thing in my attempt to get my program to compile, but nothing has worked. I'd really like to just delete everything, go back to square one and download the package again. How can I do that?

Edit: further investigation shows that there might be 2 versions of Data.Vector: 0.10.0.1 and 0.9.1, maybe they are conflicting somehow?

Edit: ghc-pkg check lists no errors, but gives me a ton of warnings that look like this:

Warning: haddock-interfaces: /Users/drewgross/.cabal/share/doc/haskell-lexer-1.0/html/haskell-lexer.haddock doesn't exist or isn't a file

Edit: GCHi also doesn't find it

λ> import Data.Vector

<no location info>:
    Could not find module `Data.Vector'
    Perhaps you meant Data.Functor (from base)
λ>

Edit: ghc-pkg list vector:

Drews-MacBook-Pro:Blokus-AI drewgross$ ghc-pkg list vector
/Library/Frameworks/GHC.framework/Versions/7.4.2-x86_64/usr/lib/ghc-7.4.2/package.conf.d
/Users/drewgross/.ghc/x86_64-darwin-7.4.2/package.conf.d
   vector-0.10.0.1
Drews-MacBook-Pro:Blokus-AI drewgross$

and building with -v flag:

Drews-MacBook-Pro:Blokus-AI drewgross$ ghc --make -O2 -prof -auto-all -v playGame
Glasgow Haskell Compiler, Version 7.4.2, stage 2 booted by GHC version 7.4.2
Using binary package database: /usr/local/Cellar/ghc/7.4.2/lib/ghc-7.4.2/package.conf.d/package.cache
Using binary package database: /Users/drewgross/.ghc/x86_64-darwin-7.4.2/package.conf.d/package.cache
package Cabal-1.16.0.3-e689d8e77b2f476229954cd43b1737bd is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd directory-1.1.0.2-72e928d14fc50f31f7e6404839a15691 unix-2.5.1.1-29636eb78541401e8e00393ef5df097e
package Tensor-1.0.0.1-a8f1a59665c3ebc4867678a14fe1460f is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd
package binary-0.5.1.1-e62c39c3aba8093e9b9655a4a8d2bce9 is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd bytestring-0.10.0.1-9b03e69060669eabf0b20e150305c7be
package bmp-1.2.3.2-c7572ec2bbb802bfd93fed0953c61d5d is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd binary-0.5.1.1-e62c39c3aba8093e9b9655a4a8d2bce9 bytestring-0.10.0.1-9b03e69060669eabf0b20e150305c7be
package bytestring-0.10.0.1-9b03e69060669eabf0b20e150305c7be is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd
package ghc-paths-0.1.0.9-4e6c624a3431a4fa7630e4fb77be4c83 is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd
package haskell-lexer-1.0-8fea1c35b626a2de761522690a88c063 is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd
package primitive-0.4.1-0007d441db5f4ce1ffd66bd3816c2d4e is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd
package split-0.2.1.1-03ec5738edb34f2e8967d25637b9392f is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd
package vector-0.10.0.1-3450daae3d9f2092020075d05481123c is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd primitive-0.5.0.1-15cdc8c11a54a78809b647af0c2975b3
wired-in package ghc-prim mapped to ghc-prim-0.2.0.0-7d3c2c69a5e8257a04b2c679c40e2fa7
wired-in package integer-gmp mapped to integer-gmp-0.4.0.0-af3a28fdc4138858e0c7c5ecc2a64f43
wired-in package base mapped to base-4.5.1.0-47f48c3ae7f8256a66a23e9dfe22eefc
wired-in package rts mapped to builtin_rts
wired-in package template-haskell mapped to template-haskell-2.7.0.0-e109822dcbed82c43f9fa60194eb64b5
wired-in package dph-seq not found.
wired-in package dph-par not found.
Hsc static flags: -fscc-profiling -static
*** Chasing dependencies:
Chasing modules from: *playGame.hs

Grid.hs:28:8:
    Could not find module `Data.Vector'
    Perhaps you meant Data.Functor (from base)
    Locations searched:
      Data/Vector.hs
      Data/Vector.lhs
*** Deleting temp files:
Deleting: 
*** Deleting temp dirs:
Deleting: 
Drews-MacBook-Pro:Blokus-AI drewgross$

This is what shell uses:

Drews-MacBook-Pro:Blokus-AI drewgross$ which ghc
/usr/bin/ghc

I did cabal install -v lens and obviously there was a ton of output but I think this is the relevant part:

Registering lens-3.7.0.2...
/usr/bin/ghc-pkg update - --global --user
Updating world file...
Drews-MacBook-Pro:Blokus-AI drewgross$

Which seems to indicate that they are using the same version. I can post more of the output of a cabal install if its relevant.

Edit: more ghc output from cabal install -v

Building lens-3.7.0.2...
Preprocessing library lens-3.7.0.2...
Building library...
creating dist/build
/usr/bin/ghc --make -package-name lens-3.7.0.2 -hide-all-packages -fbuilding-cabal-package -i -idist/build -isrc -idist/build/autogen -Idist/build/autogen -Idist/build -optP-DTRUSTWORTHY=1 -optP-DDEFAULT_SIGNATURES=1 -optP-include -optPdist/build/autogen/cabal_macros.h -odir dist/build -hidir dist/build -stubdir dist/build -package-id array-0.4.0.0-0b6c5ca7e879a14d110ca4c001dd9297 -package-id base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd -package-id bytestring-0.9.2.1-0044644a71adfe5e950e6c6f6ca13065 -package-id comonad-3.0.0.2-6ef27fce8536ebdf9c364307a0915f63 -package-id comonad-transformers-3.0-a6df581636b1c9b514cfa6560f17d6a3 -package-id comonads-fd-3.0-b906ed7898871c5d2427052e2eefa62e -package-id containers-0.4.2.1-75f143aa39a3e77a1ce2300025bdd8ce -package-id filepath-1.3.0.0-f998e5510c76a98913f57b14b4f16c57 -package-id ghc-prim-0.2.0.0-7d3c2c69a5e8257a04b2c679c40e2fa7 -package-id hashable-1.1.2.5-14291f3b4e96b5599759ce7daa2bd37c -package-id mtl-2.1.2-02e701f9b1590ee88a0b5b0bd5d93a29 -package-id parallel-3.2.0.3-4cdd6067624f867b253b98d6d9fb9f52 -package-id semigroups-0.8.4.1-4d3a86b037504e6000a0354510588745 -package-id split-0.2.1.1-03ec5738edb34f2e8967d25637b9392f -package-id template-haskell-2.7.0.0-29110cc89a711d6ab3e7ee0e0a8ee949 -package-id text-0.11.2.3-473d9a1761b27c7315f2ef4569d93c3c -package-id transformers-0.3.0.0-8e66ecc7d4dae2b07b2b5406908c70e4 -package-id unordered-containers-0.2.2.1-d70d5ccb1df11dbbbaac89571b1ee46d -package-id vector-0.10.0.1-3450daae3d9f2092020075d05481123c -O -Wall -fwarn-tabs -O2 -fdicts-cheap -funbox-strict-fields -XHaskell98 Control.Lens.TH Language.Haskell.TH.Lens Control.Exception.Lens Control.Lens Control.Lens.Action Control.Lens.Classes Control.Lens.Combinators Control.Lens.Fold Control.Lens.Getter Control.Lens.Indexed Control.Lens.IndexedGetter Control.Lens.IndexedFold Control.Lens.IndexedLens Control.Lens.IndexedSetter Control.Lens.IndexedTraversal Control.Lens.Internal Control.Lens.Internal.Zipper Control.Lens.Iso Control.Lens.Loupe Control.Lens.Plated Control.Lens.Prism Control.Lens.Representable Control.Lens.Setter Control.Lens.Simple Control.Lens.Traversal Control.Lens.Tuple Control.Lens.Type Control.Lens.WithIndex Control.Lens.Wrapped Control.Lens.Zipper Control.Lens.Zoom Data.Bits.Lens Data.ByteString.Lens Data.ByteString.Strict.Lens Data.ByteString.Lazy.Lens Data.Complex.Lens Data.Data.Lens Data.Dynamic.Lens Data.HashSet.Lens Data.IntSet.Lens Data.List.Lens Data.List.Split.Lens Data.Sequence.Lens Data.Set.Lens Data.Text.Lens Data.Text.Strict.Lens Data.Text.Lazy.Lens Data.Tree.Lens Data.Typeable.Lens Data.Vector.Lens Data.Vector.Generic.Lens GHC.Generics.Lens Data.Array.Lens System.FilePath.Lens Control.Parallel.Strategies.Lens Control.Seq.Lens Control.Lens.Internal.Combinators
[ 1 of 57] Compiling Control.Lens.Classes ( src/Control/Lens/Classes.hs, dist/build/Control/Lens/Classes.o )
[ 2 of 57] Compiling Control.Lens.Internal ( src/Control/Lens/Internal.hs, dist/build/Control/Lens/Internal.o )
[ 3 of 57] Compiling Control.Lens.Internal.Combinators ( src/Control/Lens/Internal/Combinators.hs, dist/build/Control/Lens/Internal/Combinators.o )
[ 4 of 57] Compiling Control.Lens.Indexed ( src/Control/Lens/Indexed.hs, dist/build/Control/Lens/Indexed.o )
[ 5 of 57] Compiling Control.Lens.IndexedGetter ( src/Control/Lens/IndexedGetter.hs, dist/build/Control/Lens/IndexedGetter.o )
[ 6 of 57] Compiling Control.Lens.Action ( src/Control/Lens/Action.hs, dist/build/Control/Lens/Action.o )
[ 7 of 57] Compiling Control.Lens.Setter ( src/Control/Lens/Setter.hs, dist/build/Control/Lens/Setter.o )

Edit: ghc-pkg dump

Drews-MacBook-Pro:Blokus-AI drewgross$ ghc-pkg dump | grep "id: base"
id: base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd

Answer

Daniel Fischer picture Daniel Fischer · Dec 10, 2012

Your package database is badly broken. The ghc -v output lists ten unusable packages due to missing or recursive dependencies, among them vector:

package vector-0.10.0.1-3450daae3d9f2092020075d05481123c is unusable due to missing or recursive dependencies:
  base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd primitive-0.5.0.1-15cdc8c11a54a78809b647af0c2975b3

One thing all the broken packages have in common is the missing(?) dependency

base-4.5.1.0-81d626fb996bc7e140a3fd4481b338cd

where the

wired-in package base mapped to base-4.5.1.0-47f48c3ae7f8256a66a23e9dfe22eefc

used base has a different hash.

I'm not sure how this came about, as far as I'm aware, it's impossible to reinstall base, but it looks like you have two exemplars of ghc-7.4.2, and they step on each other's toes.

ghc-pkg list uses

/Library/Frameworks/GHC.framework/Versions/7.4.2-x86_64/usr/lib/ghc-7.4.2/package.conf.d

for the global package database, while the compilation uses

Using binary package database: /usr/local/Cellar/ghc/7.4.2/lib/ghc-7.4.2/package.conf.d/package.cache

Now, it might be that at least one of the two is a symlink and they're both pointing to the same place - then your package.cache is out of sync - but

Glasgow Haskell Compiler, Version 7.4.2, stage 2 booted by GHC version 7.4.2

a GHC booted by the same version seems unusual.

Can you ascertain whether you have indeed two ghc-7.4.2 and the command line uses a different one from the one cabal uses? which ghc tells you which one the shell uses, and cabal install -v some-package outputs the command line cabal uses, including the whole path to the used GHC.

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