Ignore template-haskell generated output

[ndmitchell]

At the moment if you use the lens generator to generate prisms/lenses etc from TH, you get a lot of complaints about unused pieces.

One potential solution would be to enable adding ghc-options: -ddump-splices and exclude things generated by TH, if the files exist. Downside is people won't do this by default, so it's very much an opt-in experience.

[ndmitchell]

Weeder 2.0 is being developed at https://github.com/ocharles/weeder so I suggest you go see if that fixes your issues.