Contradictory errors on C++ Class (it is and it is not a const variable)

Asked Feb 09 '22 at 11:25

Active Feb 09 '22 at 13:40

Viewed 30 times

I have a class where I define my variable "int _remaining = 52;" When I try to create an array inside of by class method Deck::shuffle() using this variable I get an error. I can only assign const.

So I tried to add a temporary const variable "const int n = Deck::_remaining" and try to create my array with array[n][2]

My compiler stills complain that it is not const.

So I try to do a "++n;" just to test it. And here I got a contradictory error that now my "n" is const...

What am I missing?

Many thanks!

class Deck {
     int _remaining = 52;

public:
     Deck();

}

void Deck::shuffle_deck() {

    const int n = Deck::_remaining; // creating a const tmp value
    n++;  // Error that n is a const (I expected that)
    char* deck_tmp[n][2]; // Error that n cannot be assigned since it is not a const

}

edited Feb 09 '22 at 13:40

prapin

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asked Feb 09 '22 at 11:25

Raphael G

1

Standard C++ does not allow VLA:s. Use `std::vector`s instead – Ted Lyngmo Feb 09 '22 at 11:26
1

And please format your code properly (like I just did for you, but you reverted it) – Ted Lyngmo Feb 09 '22 at 11:27
1

I suspect you are misreading the error. But since you did not post the error *verbatim*, it's difficult to say for sure. – Eljay Feb 09 '22 at 13:59
1

A "core constant expression" is not the same thing as a "`const` variable" – Caleth Feb 09 '22 at 14:47
If this had worked, you'd be fine: `constexpr int n = Deck::_remaining;` – Ted Lyngmo Feb 09 '22 at 17:59

Contradictory errors on C++ Class (it is and it is not a const variable)

0 Answers0