Nested block comments are elided

[sjakobi]

For example, in these haddocks, the following bit within a haddock {-|--}-comment,

For example,

> { {- A -} x {- B -} : {- C -} T }

... or

> { {- A -} x {- B -} = {- C -} T }

will be instantiated as follows:

…is rendered like this:

For example,

{ x : T }
... or

{ x = T }

The nested block comments like {- A -} and {- B -} are missing.

[sjakobi]

As a workaround, one can use line comment syntax (--|) to ensure that internal block comments are preserved. (See dhall-lang/dhall-haskell#2098 for an example.)

[andreasabel]

I found that this also concerns pragmas, e.g.

{-| ...

> {-# FOREIGN GHC import Prelude (Char, Double, Integer, String) #-}
> {-# FOREIGN GHC import qualified Data.Text #-}
> {-# FOREIGN GHC import qualified CPP.Abs #-}
> {-# FOREIGN GHC import CPP.Print (printTree) #-}
>
> data Ident : Set where
>   ident : #String → Ident

-}

just drops all the pragmas in the rendering (apologies for the Agda syntax...).

[sjakobi]

https://gitlab.haskell.org/ghc/ghc/-/issues/20336 is related.