The TypeApplications extension

  • Exploring in GHCi
  • Clarifying point-free functions
  • Resolving type ambiguity
  • Increasing type safety

TypeApplications allows you to instantiate one or more of a polymorphic function’s type arguments to a specific type. Use the @ keyword to apply the function to a type. This has a lot of benefits both for learning and for writing code.

The TypeApplications GHC extension first appeared in GHC 8.0.GHC documentation for TypeApplications.