OC self注意事项

 #import <Foundation/Foundation.h>

 @interface Person : NSObject
 - (void)test;
 + (void)test;

 - (void)test1;
 + (void)test2;

 - (void)haha1;

 + (void)haha2;

 @end

 @implementation Person
 - (void)test
 {
     NSLog(@"调用了-test方法");

     // 会引发死循环
     //[self test];
 }

 + (void)test
 {
     NSLog(@"调用了+test方法");

     // 会引发死循环
     //[self test];
 }

 - (void)test1
 {
     [self test]; // -test
 }

 + (void)test2
 {
     [self test]; // +test
 }

 - (void)haha1
 {
     NSLog(@"haha1-----");
 }

 void haha3()
 {

 }

 + (void)haha2
 {
     // haha3();
     [self haha3];
     // [self haha1];
 }
 @end

 int main()
 {
     [Person haha2];
     //Person *p = [Person new];

     //[p test1];
     return ;
 }