ios - What happens if the init method of a singleton class is called before the +sharedInstance method..? -

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what happens if init method of singleton class called before +sharedinstance method..? result in new object , if not how same instance returned ? fact static variable declared inside sharedinstance have effect on overall outcome..?

+ (libraryapi*)sharedinstance {     // 1     static libraryapi *_sharedinstance = nil;      // 2     static dispatch_once_t oncepredicate;      // 3     dispatch_once(&oncepredicate, ^{         _sharedinstance = [[libraryapi alloc] init];     });     return _sharedinstance; }

in objective-c init method of class method 'init' prefix. it's 1 of biggest differences between objc , swift. if call init method bad you'll no doubt init new instance when init method return successfully.

a static variable inside function keeps value between invocations. every time method sharedinstance called give same instance. more static variable check out here


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