NOTE: this package is not compatible with Elm 0.19.1
Functions to verify properties of a Set.
Fails if a Set is empty.
import Set notEmpty "error" <| Set.empty --> Err [ "error" ] notEmpty "error" <| Set.fromList [ (1, 1) ] --> Ok <| Set.fromList [ (1, 1) ]
Fails if a Set is empty.