Instructions to file a bug report
If you see this message: eta.exe: panic! (the 'impossible' happened), then you have definitely found a bug in the compiler. It's also possible that your code is not well-typed, but if you see this message, please fill a bug report on the Eta GitHub repository.
If you see a compiler error message confuses you, that's a bug too. We are working on improving error messages. please fill a bug report on the Eta GitHub repository.
If you don't have enough time for a search, then don't worry about that. Just submit the bug. If it's a duplicate, somebody will notice that and close it.
If you have the time for it, it would be great if you could search the issue tracker to see if there is an existing bug similar to your problem. If there is, and it's an open bug, you can comment on that issue and say you are also affected. We will prioritize such bugs.
It helps our diagnosis to include the following:
Etlas gives this error message when running etlas test with missing dependencies:etlas: Encountered missing dependencies: HUnit -any, hspec >=1.3, mockery -any, temporary -any Run 'etlas install --dependencies-only' to install the dependencies.
It should suggest to add the --enable-tests flag.