append(_:)
Append a new usage
to the end of the ExtendedKeyUsage
, if it doesn’t already contain it.
@discardableResult mutating func append(_ usage: Element) -> (inserted: Bool, index: Int)
Parameters
Returns
A pair (inserted, index)
, where inserted
is a Boolean value indicating whether the operation added a new element, and index
is the index of usage
in the resulting ExtendedKeyUsage
.