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c++assertfriend

assert as a friend class

I can not declare neither assert class, nor assert function as a friendly to my class.

Am I right with such a declaration?

class Baka
{
private:
friend assert;          //invalid friend declaration
friend void assert();   //expected an identifer
public:
}

I've already googled a lot, but I can't find right arguments for assert() and the real name of the "assert" class( I will appreciate any help.

Solution

  • assert isn't a function, it's a macro. Therefore if you have <cassert> included upstream it will be expanded by the pre-processor before compilation

    // cassert file
// Not debug version
#define assert(_Expression)     ((void)0)

    So your class actually says

    class Baka
{
private:
  friend ((void)0);          //invalid friend declaration
  friend void ((void)0)();   //expected an identifer
public:
}

    Which obviously shouldn't compile.