I don’t know about the candidates But the uptimeNanoseconds is a UInt64 and as such you should probably use substractWithOverflow.
var a: UInt64 = 12 var b: UInt64 = 25 let result = UInt64.subtractWithOverflow(a, b) if result.overflow { print("Overflow") } else { let answer = result.0 } Regards, Rien Site: http://balancingrock.nl Blog: http://swiftrien.blogspot.com Github: http://github.com/Balancingrock Project: http://swiftfire.nl > On 16 Feb 2017, at 16:56, J.E. Schotsman via swift-users > <swift-users@swift.org> wrote: > > Hello, > > I am trying to define an operator that subtracts dispatch times: > > #import Dispatch > > func -( time1: DispatchTime, time2: DispatchTime ) -> DispatchTimeInterval > { > return DispatchTimeInterval.nanoseconds( time2.uptimeNanoseconds - > time1.uptimeNanoseconds ) > } > > Compiler says: Ambiguous use of operator ‘-' > Found this candidate > Found this candidate > > As usual the candidates are unknown. > > What am I doing wrong? > > Jan E. > _______________________________________________ > swift-users mailing list > swift-users@swift.org > https://lists.swift.org/mailman/listinfo/swift-users _______________________________________________ swift-users mailing list swift-users@swift.org https://lists.swift.org/mailman/listinfo/swift-users