[web-devel] [Yesod] failed : cabal install yesod-examples

I'll install yesod-examples. But cabal install yesod-examples failed. Error Messages are here. ---- Linking dist/build/form/form ... yesod/tutorial/mkToForm.hs:11:7: Could not find module `MkToForm': Use -v to see a list of the files searched for. cabal: Error: some packages failed to install: yesod-examples-0.6.0 failed during the building phase. The exception was: ExitFailure 1 --- The mkToForm.hs's line 11 is 'import MkToForm'. You success to compile this?