NSLog is unavailable

问题

I have following function:

func myNSLog(_ givenFormat: String, _ args: CVarArg..., _ function:String = #function) {
        let format = "\(function): \(givenFormat)"
        NSLog(format, args)

Wich result in the following error: 'NSLog' has been explicitly marked unavailable here (Foundation.NSLog)

Within the documentation is it explicit listed as available. What do I miss?

回答1:

Similar as in C, you cannot pass a variable argument list directly to another function. You have to create a CVaListPointer (the Swift equivalent of va_list) and pass that to the NSLogv variant:

func myNSLog(_ givenFormat: String, _ args: CVarArg..., _ function:String = #function) {
    let format = "\(function): \(givenFormat)"
    withVaList(args) { NSLogv(format, $0) }
}

(Swift 3 code.)

来源：https://stackoverflow.com/questions/37993693/nslog-is-unavailable