046.@try 处理异常

--------------- FKEatable.h ---------------
#import
<Foundation/Foundation.h>

@protocol
FKEatable

@optional

-(void) taste;
@end
---------------
FKApple.h ---------------
#import
"FKEatable.h"

@interface
FKApple :
NSObject <FKEatable>
@end
--------------- FKApple.m
---------------
#import
"FKApple.h"

@implementation
FKApple
@end
---------------
main.m
---------------
#import
<Foundation/Foundation.h>
#import
"FKApple.h"

int
main()

{

FKApple* app = [[FKApple
alloc]
init];

[app
taste];
}

一、运行以上代码会出现如下错误：
-[FKApple taste]: unrecognized selector sent to instance 0x10030e540
*** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[FKApple taste]: unrecognized selector sent to instance 0x10030e540'

二、本节代码涉及到的知识点：
1.错误原因：FKEateble协议中的taste方法没有实现。
2.下一节将介绍如何捕捉异常。