小编aal*_*vic的帖子

Why is the first expression allowed, but the second not:

void test()
{
   int a;

   ++a = getSomeInt();
   a++ = getSomeInt();
}

I mean, why its forbidden for the second one to be an lvalue? The second one makes sense and the first not. In the first one we increment the variable and immediately after we gave here a new value, we lose it. That's not the case in the second expression. It makes sense to assign some value …

我有一个表 user_synonyms，我可以在其中看到名称、表和表所有者。有没有办法查看这个同义词是否仍然有效，即 如果不手动尝试引用表仍然存在？