hledger-web not compatible with new data-default-0.8.0.0

[thielema]

When compiling hledger-web I get:

[ 1 of 18] Compiling Hledger.Web.Settings ( Hledger/Web/Settings.hs, interpreted )

Hledger/Web/Settings.hs:87:5: error: [GHC-39999]
    • No instance for ‘Data.Default.Internal.Default
                         WidgetFileSettings’
        arising from a use of ‘def’
    • In the expression: def
      In a record update at field ‘wfsHamletSettings’,
      with type constructor ‘WidgetFileSettings’
      and data constructor ‘Yesod.Default.Util.WidgetFileSettings’.
      In the expression:
        def
          {wfsHamletSettings = defaultHamletSettings
                                 {hamletNewlines = AlwaysNewlines}}
   |
87 |     def -- Yesod.WidgetFileSettings
   |     ^^^

Problem is data-default-0.8.0.0 that was released yesterday. It does no longer re-export Default class from data-default-class. This is a breaking change, indeed the major version bump to 0.8 indicates that. yesod defines Default instance for data-default-class, not data-default. I asked the author of both packages, what package we shall prefer in the future:
mauke/data-default#29

[simonmichael]

Thanks. (I've sent you a github repo collaborator invitation, eg to allow more issue management powers if needed.)

[simonmichael]

@thielema do you know if there's anything we still need to do with bounds in hledger-web to avoid data-default-related build problems ?

My local build, and current stackage nightly, seem to be working without problems using

data-default-0.8.0.0
data-default-class-0.2.0.0