objective-c 2.0的字面量Literals

#import <Foundation/Foundation.h>

int main(void){
@autoreleasepool{
NSString *str0 = @"hello";
NSString *str1 = [NSString stringWithFormat:@"%@",@"hello"];
NSLog(@"%@ %@",str0,str1);
if(str0 == str1)
NSLog(@"str0 == str1");
if([str0 isEqual:str1])
NSLog(@"str0 equal str1");
if([str0 compare:str1] == NSOrderedSame)
NSLog(@"str0 compare str1 is Same");
NSMutableSet *set = [NSMutableSet new];
NSLog(@"count %lu at begin",[set count]);
[set addObject:str0];
[set addObject:str1];
[set addObject:[str0 stringByAppendingString:str1]];
NSLog(@"count %lu at now",[set count]);
NSLog(@"%@",set);
//NSLog(@"%@ %@",set[0],set[2]);
NSMutableDictionary *dict = [[NSMutableDictionary alloc] init];
[dict setDictionary:@{@1:@1,@2:@"hh",@"hi":@1}];
dict[@11] = @"what!?";
NSLog(@"%@ : %@",dict[@1],dict);

NSMutableArray *ary = [NSMutableArray arrayWithArray:@[@1,@2,@"hehe"]];
NSLog(@"%@",ary);
ary[2] = @"smile!";
NSLog(@"%@ : %@",ary[0],ary);

@try{
NSLog(@"value with bad index: %@",ary[11]);
NSLog(@"never see me!");
}
@catch(NSException *e){
NSLog(@"caught %@:%@",[e name],[e reason]);
}
@finally{
NSLog(@"at last!!!");
}
}
return 0;
}