In #206, we left some work unfinished, for one reason or another.

• After the patch that solved Template Haskell expressions in Unicode mathematical white square brackets are formatted differently than in ASCII brackets. tweag/ormolu#934 is merged into fourmolu, we can add the handling of ⟦ ⟧ brackets.
• We can improve the code along the way, as mentioned in code review. Namely:
  • Do not export whenUnicodeOtherwise.
  • Put more elegant code here:

    fourmolu/src/Ormolu/Printer/Combinators.hs

    Lines 192 to 193 in 44389c1

    	UnicodeDetect | unicodeExtensionIsEnabled -> unicodeText
    	UnicodeDetect | otherwise -> asciiText

I think that sums it up.

Do ping me if I forget. In all likelihood I shall forget.