Stopped in , _exception :: e = GHC.Exception.Type.SomeExceptionWithBacktrace (GHC.Exception.Type.SomeException (GHC.Exception.ErrorCallWithLocation ...)) [] :steplocal is not possible. Cannot determine current top-level binding after a break on error / exception. Use :stepmodule. Stopped in , _exception :: e = GHC.Exception.Type.SomeExceptionWithBacktrace (GHC.Exception.Type.SomeException (GHC.Exception.ErrorCallWithLocation ...)) [] :steplocal is not possible. Cannot determine current top-level binding after a break on error / exception. Use :stepmodule.