IOS---blcok (intercepted automatic variables)

First two pieces of code:

//1val0;void (^blk)(void) = ^{val1};

//2id array = [[NSMutableArray alloc] init];void (^blk)(void) = ^{    id obj = [[NSObject alloc] init];    [array addobject:obj];};

A little use block of the students know that the first program compile error, because the program to intercept the code assigned value (if you want to negative, you need to add _block, into the _block variable), and the second code will not error, if the C language to describe, That is to intercept the Nsmutablearray class object with the struct instance pointer, although cannot assign the value, but the use is no problem

IOS---blcok (intercepted automatic variables)