RegexPattern.Options.remove(_:)

In the following example, the priority shipping option is removed from the options option set. Attempting to remove the same shipping option a second time results in nil, because options no longer contains priority as a member.

var options: ShippingOptions = [.secondDay, .priority] let priorityOption = options.remove(.priority) print(priorityOption == .priority) // Prints "true"

print(options.remove(.priority)) // Prints "nil"

In the next example, the express element is passed to remove(_:) . Although express is not a member of options , express subsumes the remaining secondDay element of the option set. Therefore, options is emptied and the intersection between express and options is returned.

let expressOption = options.remove(.express) print(expressOption == .express) // Prints "false" print(expressOption == .secondDay) // Prints "true"

• Parameter member: The element of the set to remove.
• Returns: The intersection of [member] and the set, if the intersection was nonempty; otherwise, nil.