Hi, `ghc`, without any extension enabled, permits an infix function lo begin with `@`, like: ``` haskell > let a @: b = a > 3 @: 4 3 ``` However, when parsing it with `haskell-src-exts-1.18.2`, we have (as mentioned in https://github.com/chrisdone/hindent/issues/226): ``` haskell > fmap (const ()) (parseExpWithMode parseMode "p @Int") ParseOk () > fmap (const ()) (parseExpWithMode parseMode "p @: q") ParseFailed (SrcLoc "<unknown>.hs" 1 4) "Parse error: :" ```