A simple way to make your NSLogs and NSAsserts more informative

2007-06-13 22:44:28 UTC

OK, so I’m not totally radio-silent. I learned about this in a WWDC session, but since it’s already public API in Tiger (actually, it’s a GCC extension), I can talk about it.

It’s a built-in macro called __PRETTY_FUNCTION__. This is a fully-qualified human-readable signature of the function you’re in. The GCC docs don’t mention this part, but it even works in Objective-C, in addition to C++ and plain C. Here’s a test app, containing this code:

@implementation Blah(blah)
- (void)blah {
    NSLog(@"%s", __PRETTY_FUNCTION__);
}
@end

And the output:

2007-06-14 07:50:37.733 printmethod[1800] -[Blah(blah) blah]

Notice that it includes the class name, category name (if any), and method selector.

Note that that’s a C-string, not an NSCFString. Be sure to set up your format string accordingly.

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