Common Errors: Brittany

Unknown syntactical constructs

ERROR: encountered unknown syntactical constructs:
HsSpliceE{}

Brittany (as of v0.11.0.0) doesn't handle Template Haskell (among other things), and generates the above error when it sees it. The solution is to ignore the offending files.

---
- brittany:
    include:
      - "**/*.hs"
      - "!src/MyBadFile.hs"

Alternative, you can disable the offending expression in the Haskell source

-- brittany-disable-next-binding

someFunction =
  [someQuote|
    someText
  |]

-- brittany-disable-next-binding

someOtherFunction =
  $(someOtherQuote "someText")

Note that disable-next-binding on works on top-level bindings. Attractive as it may be, you can't disable a specific binding within a where or let.

Restyled keeps removing shebangs

If you edit a "Stack Script", you will find that Restyled (through Brittany) really wants to strip that shebang.

This is an open issue: https://github.com/lspitzner/brittany/issues/192

Unfortunately, you must exclude such files via .restyled.yaml.