Wrap calls to NSLog in Objective-C

Question

I want to be able to wrap all calls to NSLog in my Class so I can have a single place to enable/disable logging.

I can't figure out how to accept variable numbers of arguments to my method and then hand them on to NSLog.

Examples, please.

Answer 1

for a logger I'd just go with a macro

#if DEBUG
#warning LOGGING ENABLED
#define DebugLog(fmt, ...) NSLog((@"%s " fmt), __PRETTY_FUNCTION__, ##__VA_ARGS__)

#else
#define DebugLog(...)

#endif

BUT

if you want to work with variable arguments:

declare your method as so it takes a variable number of arguments

+ (id)stringWithFormat:(NSString *)format, ...;

use the va_* C functions to interact with the variable arguments

• va_start - Initializes a va_list
• va_arg - Fetches the next argument out of the list.
• va_end - Releases any memory by the list of vas

---

DEMO for the logging

#import <Foundation/Foundation.h>

#define DEBUG 1

#if DEBUG
#warning LOGGING ENABLED
#define DebugLog(fmt, ...) NSLog((@"%s " fmt), __PRETTY_FUNCTION__, ##__VA_ARGS__)

#else
#define DebugLog(...)

#endif

int main(int argc, char *argv[]) {
    @autoreleasepool {
                    id v = @1;
        DebugLog(@"bla: %@", v);        
    }
}