Question

I am trying to install the “yi” editor using cabal-install, which in turns installs the package ‘derive-2.3.0.2’. I get the following error during derive’s compilation:

[53 of 58] Compiling Data.Derive.Internal.Traversal ( Data/Derive/Internal/Traversal.hs, dist/build/Data/Derive/Internal/Traversal.o )

Data/Derive/Internal/Traversal.hs:34:0:
    Illegal instance declaration for `Applicative (Writer w)'
        (All instance types must be of the form (T t1 ... tn)
         where T is not a synonym.
         Use -XTypeSynonymInstances if you want to disable this.)
    In the instance declaration for `Applicative (Writer w)'
cabal: Error: some packages failed to install:
derive-2.3.0.2 failed during the building phase. The exception was:
ExitFailure 1

Of course, I tried to build it with –ghc-option=-XTypeSynonymInstances, which in turn gives another compilation error.

I am using ubuntu maverick 32-bit, with ghc-6.12.1 and cabal-install 0.8.2. The ghc was installed from the package repository. Cabal was installed using:

cabal-install cabal

Alex.

Answer 1

I would consider reporting a bug or asking on the [e-mail] adress. This is supposed to be a misstake. You can probably also try to install one of the older versions from Hackage.