[web-devel] Yesod devel error: Yesod: panic! System/Plugins.hs:(84, 14)-(86, 29): Non-exhaustive patterns in lambda

vagif.verdi at gmail.com vagif.verdi at gmail.com
Tue Apr 26 02:21:55 CEST 2011

Completely fresh install of yesod 0.8
I migrated my application successfully. It builds and works fine.

But when trying yesod devel i get this error:

yesod: panic! (the 'impossible' happened)
  (GHC version 7.0.2 for x86_64-unknown-linux):
        System/Plugins.hs:(84,14)-(86,29): Non-exhaustive patterns in lambda

Also cabal gives me following warning on configure: 

Warning: This package indirectly depends on multiple versions of the same
package. This is highly likely to cause a compile failure.
package haskell-src-meta-0.3 requires syb-0.2.2
package aeson- requires syb-0.3

Not sure if its related to the error in any way, but it does not affect the 
build, and my executable works fine.

Vagif Verdi

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