so why do you prefix instance variables with an underscore ("_delegate") and nevertheless use "delegate" inside the method, Scott? This kind of naming conventions are very confusing to me
A leading underscore usually means "private." All instance variables are implicitly private in Objective-C, so many experienced user simply prefix all of them with an underscore. Part of the reason is to avoid confusion with local variables. For example, take a look at this:
This is, at best, simply confusing. Is the delegate declared in talkToDelegate a local variable or does it refer to the instance variable? If you add an underscore to the instance variable, you can easily tell the two apart.
by Scott Stevenson — Jan 21
A leading underscore usually means "private." All instance variables are implicitly private in Objective-C, so many experienced user simply prefix all of them with an underscore. Part of the reason is to avoid confusion with local variables. For example, take a look at this:
@interface DefinesTest : NSObject { id delegate; } @end @implementation DefinesTest - (void) talkToDelegate { id delegate = nil; } @endThis is, at best, simply confusing. Is the delegate declared in talkToDelegate a local variable or does it refer to the instance variable? If you add an underscore to the instance variable, you can easily tell the two apart.