Operator
-=(_:_:)
iOS 8.0+
iPadOS 8.0+
Mac Catalyst 8.0+
macOS 10.10+
tvOS 9.0+
watchOS 2.0+
Subtract a
TimeInterval from a Date.static func -= (lhs: inout Date, rhs: TimeInterval)Discussion
Warning
This only adjusts an absolute value. If you wish to add calendrical concepts like hours, days, months then you must use a Calendar. That will take into account complexities like daylight saving time, months with different numbers of days, and more.