PropCheck.BasicTypes.union

You're seeing just the function union, go back to PropCheck.BasicTypes module for more information.

Specs

union([raw_type(), ...]) :: type()

The union of all types in list_of_types.

list_of_types can't be empty. The random instance generator is equally likely to choose any one of the types in list_of_types. The shrinking subsystem will always try to shrink an instance of a type union to an instance of the first type in list_of_types, thus you should write the simplest case first.