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| #define SINGLETON_INTERFACE(className) + (instancetype)shared##className;
#define SINGLETON_IMPLEMENTATION(className) \
static id instance; \
+ (instancetype)allocWithZone:(struct _NSZone *)zone { \
static dispatch_once_t onceToken; \
dispatch_once(&onceToken, ^{ \
instance = [super allocWithZone:zone]; \
}); \
return instance; \
} \
\
+ (instancetype)shared##className { \
static dispatch_once_t onceToken; \
dispatch_once(&onceToken, ^{ \
instance = [[self alloc] init]; \
}); \
return instance; \
} \
\
- (id)copyWithZone:(NSZone *)zone { \
return instance; \
}
|