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@interface RootObject
+ (instancetype)alloc;
- (instancetype)init;
@end
@interface BaseClass : RootObject
+ (instancetype)sharedInstance;
- (instancetype)initWithFoo:(int)foo;
@end
static BaseClass *sharedInstance = (void *)0;
static int counter = 0;
@implementation BaseClass
+ (instancetype)sharedInstance {
if (sharedInstance) {
return sharedInstance;
}
sharedInstance = [[BaseClass alloc] initWithFoo:3];
return sharedInstance;
}
- (instancetype)initWithFoo:(int)foo {
self = [super init];
if (self) {
counter += foo;
}
return self;
}
@end
|
