Singleton Tuple

Version on this page:
LTS Haskell 22.29:0.4.2
Stackage Nightly 2024-07-20:0.4.2
Latest on Hackage:0.4.2

See all snapshots OneTuple appears in

BSD-3-Clause licensed by John Dorsey
Maintained by Oleg Grenrus, John Dorsey
This version can be pinned in stack with:OneTuple-,2539

Module documentation for

This package is a compatibility package for a singleton data type

data Solo a = MkSolo a

Note: it's not a newtype

Solo is available in base-4.16 (GHC-9.2).


  • Support GHC-7.2 and GHC-7.0.


  • Mark MkSolo pattern synonym as COMPLETE


  • Rename constructor to MkSolo as in base-4.17. The compatibility pattern synonym is provided.
  • Add Foldable1 Solo instance


  • Add Data.Tuple.Solo.TH with tupE using Solo from this package
  • Add Hashable and Hashable1 instances
  • Drop GHC-7.0 and GHC-7.2 support


  • Rename OneTuple to Solo
  • Add Typeable, Data, MonadZip, Eq1, Ord1, Show1, Read1, Generic and Generic1 instances

  • Compatible with GHC-8.6


  • Add Semigroup instances
  • Compatible with GHC-8.4