Build failure with mtl-2.3

[sjakobi]

Building library for pretty-types-0.4.0.0..
[1 of 1] Compiling Data.Type.Pretty ( src/Data/Type/Pretty.hs, dist/build/Data/Type/Pretty.o, dist/build/Data/Type/Pretty.dyn_o )

src/Data/Type/Pretty.hs:632:9: error:
    Variable not in scope:
      when
        :: Bool
           -> PTM ()
           -> RWST
                Indentation String PTRenderState Data.Functor.Identity.Identity a1
    |
632 |         when leftHasContent (ptShow (Proxy :: Proxy l))
    |         ^^^^

src/Data/Type/Pretty.hs:633:9: error:
    Variable not in scope:
      when
        :: Bool
           -> PTM ()
           -> RWST
                Indentation String PTRenderState Data.Functor.Identity.Identity a0
    |
633 |         when (leftHasContent && rightHasContent) (ptShow (Proxy :: Proxy sep))
    |         ^^^^

src/Data/Type/Pretty.hs:634:9: error:
    Variable not in scope:
      when
        :: Bool
           -> PTM ()
           -> RWST
                Indentation String PTRenderState Data.Functor.Identity.Identity ()
    |
634 |         when rightHasContent (ptShow (Proxy :: Proxy r))
    |         ^^^^

src/Data/Type/Pretty.hs:645:9: error:
    Variable not in scope:
      when
        :: Bool
           -> RWST
                Indentation String PTRenderState Data.Functor.Identity.Identity ()
           -> RWST
                Indentation String PTRenderState Data.Functor.Identity.Identity ()
    |
645 |         when hasContent $ do
    |         ^^^^

src/Data/Type/Pretty.hs:658:9: error:
    Variable not in scope:
      when
        :: Bool
           -> RWST
                Indentation String PTRenderState Data.Functor.Identity.Identity ()
           -> RWST
                Indentation String PTRenderState Data.Functor.Identity.Identity ()
    |
658 |         when hasContent $ do
    |         ^^^^

[sheyll]

Hi thanks for the issue, I will look into it.

[sjakobi]

Note that mtl-2.3 ended up being deprecated due to haskell/mtl#117. I hope that there will be a follow-up release in a few weeks.