yesodweb/yesod — Issue #189: yesod-json 0.2.2.1 fails to build with aeson 0.5 
Author: wjt
Created: 2011-12-24 11:53:58+00:00
State: open

aeson 0.5 has API changes relative to 0.4, which leads to a build failure in yesod-json:

Resolving dependencies...
Configuring yesod-json-0.2.2.1...
Preprocessing library yesod-json-0.2.2.1...
Building yesod-json-0.2.2.1...
[1 of 1] Compiling Yesod.Json ( Yesod/Json.hs, dist/build/Yesod/Json.o )

Yesod/Json.hs:38:47:
Couldn't match expected type `blaze-builder-0.3.0.2:Blaze.ByteString.Builder.Internal.Types.Builder'
with actual type `Data.Text.Lazy.Builder.Builder'
Expected type: J.Value
-> blaze-builder-0.3.0.2:Blaze.ByteString.Builder.Internal.Types.Builder
Actual type: J.Value -> Data.Text.Lazy.Builder.Builder
In the second argument of `(.)', namely `fromValue'
In the expression: flip ContentBuilder Nothing . fromValue
cabal: Error: some packages failed to install:
yesod-json-0.2.2.1 failed during the building phase. The exception was:
ExitFailure 1