Compilation failure due to missing Show instance

[snoyberg]

Running:

cabal install diagrams-haddock --constraint 'diagrams-builder==0.4.2'

Results in:

src/Diagrams/Haddock.hs:454:9:
    No instance for (Show (Options SVG Diagrams.TwoD.Types.R2))
      arising from a use of `buildDiagram'
    Possible fix:
      add an instance declaration for
      (Show (Options SVG Diagrams.TwoD.Types.R2))
    In a stmt of a 'do' block:
      buildDiagram
        SVG
        zeroV
        (SVGOptions (mkSizeSpec w h) Nothing)
        (map (view codeBlockCode) neededCode)
        (url ^. diagramName)
        []
        ["Diagrams.Backend.SVG"]
        (hashedRegenerate (\ _ opts -> opts) cacheDir)
    In the second argument of `($)', namely
      `do { createDirectoryIfMissing True cacheDir;
            when (not dataURIs) $ createDirectoryIfMissing True outputDir;
            logStr $ "[ ] " ++ (url ^. diagramName);
            IO.hFlush IO.stdout;
            .... }'
    In a stmt of a 'do' block:
      res <- liftIO
             $ do { createDirectoryIfMissing True cacheDir;
                    when (not dataURIs) $ createDirectoryIfMissing True outputDir;
                    logStr $ "[ ] " ++ (url ^. diagramName);
                    IO.hFlush IO.stdout;
                    .... }
Failed to install diagrams-haddock-0.2.1.6
cabal: Error: some packages failed to install:
diagrams-haddock-0.2.1.6 failed during the building phase. The exception was:
ExitFailure 1

[byorgey]

Whoops, sorry, I'm in the middle of updating some packages and thought (incorrectly) that I had reached a stable stopping point. I know exactly what the problem is, an updated diagrams-haddock will follow later today. Thanks for the report!

[snoyberg]

No problem, hopefully the report was helpful. I've been in this exact situation plenty of times before :)

[byorgey]

Fixed by diagrams-haddock-0.2.2.