Version history

We follow Semantic Versions since the 0.1.0 release.

Version 0.4.1


  • Fixes typing_extensions version resolution

Version 0.4.0


  • Breaking: removes is_protocol boolean argument from .instance, now use protocol=YourProtocol instead

  • Adds support for concrete generic types like List[str] and Set[int] #24

  • Adds support for types that have __instancecheck__ defined via delegate argument #248

  • Adds support for multiple type arguments in Supports type #244


  • Fixes that types referenced in multiple typeclasses were not handling Supports properly #249

  • Fixes typing bug with ABC and mutable typeclass signature #259

  • Fixes that mypy plugin was failing on calling a typeclass without arguments #270

Version 0.3.0


  • Breaking: drops python3.6 support

  • Breaking: now requires typing_extensions>=3.10 and mypy>=0.902

  • Breaking: now classes traverses mro of registered types and fallbacks to super-types if some type is not registered

  • Adds generic typeclasses

  • Adds caching to runtime type dispatch, it allows to call already resolved instances way faster

  • Adds better typeclass validation during mypy typechecking

  • Adds .supports() method to typeclass to check if some instance is supported in runtime

  • Makes .supports() a typeguard

  • Adds Supports type

  • Adds AssociatedType variadic type


  • Improves docs

Version 0.2.0


  • Breaking: renames mypy typeclass_plugin to classes_plugin

  • Adds python3.9 support


  • Updates dependencies

Version 0.1.0

  • Initial release