Is extern keyword really necessary?

Posted by httpinterpret on Stack Overflow See other posts from Stack Overflow or by httpinterpret
Published on 2010-05-15T13:09:26Z Indexed on 2010/05/15 13:14 UTC
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c++

|

extern

...
#include "test1.h"

int main(..)
{
    count << aaa <<endl;
}

aaa is defined in test1.h,and I didn't use extern keyword,but still can reference aaa.

So I doubt is extern really necessary?

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