An easy way of dealing with dispatch time in Swift 3 (from https://github.com/Thomvis/BrightFutures/blob/xcode8b5/BrightFutures/Number+BrightFutures.swift)

DispatchTime.swift

public extension Int {
    
    public var seconds: DispatchTimeInterval {
        return DispatchTimeInterval.seconds(self)
    }
    
    public var second: DispatchTimeInterval {
        return seconds
    }
    
    public var milliseconds: DispatchTimeInterval {
        return DispatchTimeInterval.milliseconds(self)
    }
    
    public var millisecond: DispatchTimeInterval {
        return milliseconds
    }
    
}

public extension DispatchTimeInterval {
    public var fromNow: DispatchTime {
        return DispatchTime.now() + self
    }
}

// Example:

DispatchQueue.main.asyncAfter(deadline: 3.seconds.fromNow) {
    // do something
}

// Instead of:

DispatchQueue.main.asyncAfter(deadline: DispatchTime.now() + DispatchTimeInterval.seconds(3)) {
    // do something
}