initialization of 'element' is skipped by 'case' label

Question

I don't understand why I am getting the error:

initialization of 'element' is skipped by 'case' label.

Can someone please explain to me?

void LinkedList::process_example(int choice) {
    switch(choice) {
    case 1:
        cout << endl << endl << "Current S = ";
        this->printSet();

        cout << "Enter an element :";
        char* element = "lol";

        //cin>>element;
        cin.clear();
        cin.ignore(200, '\n');

        this->Addelementfromback(element); //error is here
        cout << endl << endl << "Current S = ";

        this->printSet();
        break;

    case 2:
        this->check_element();
        break;

    case 3:
        cout << endl << endl;
        cout << "Current Set S = ";
        this->printSet();

        cout << endl << "S has ";
        int count = this ->check_cardinality();
        cout << count << " elements";
        break;
    }
}

That error is pretty clear, also very odd use of a switch statement. — Rapptz, Feb 03 '13 at 04:21
Each `case` does not introduce a new scope (only `{ }` blocks do that). So when you declare a variable inside one case, it should put be within its own block. — Cameron, Feb 03 '13 at 04:29

score 169 · Accepted Answer · edited May 23 '17 at 12:10

169

Try wrap case with {}, and put all your statement inside {}.

case 1:
{
   cout << endl << endl << "Current S = ";
   this->printSet();    
   // and other mess
}
break;

You should put all these statement in functions, keep case statement clear. For example, write this style:

case 1:
   initializeElement();
   break;
case 2:
   doSomethingElse();
   break;

See link

edited May 23 '17 at 12:10

Community

1
1

answered Feb 03 '13 at 04:24

billz

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10

@billiz why does putting the { } solve the problem??? – Computernerd Feb 03 '13 at 04:30
22

scope issue, `case:` doesn't introduce new scope till `break`, so you have to use `{}` – billz Feb 03 '13 at 04:34
2

I still dont quite understand , any article i can read to better understand??? – Computernerd Feb 03 '13 at 04:38
4

http://stackoverflow.com/questions/92396/why-cant-variables-be-declared-in-a-switch-statement – billz Feb 03 '13 at 04:48
brilliant. putting inside solved the issue – Justin Mathew Apr 11 '23 at 11:27

score 15 · Answer 2 · edited Sep 29 '17 at 11:30

When a variable is declared in one case, the next case is technically still in the same scope so you could reference it there but if you hit that case without hitting this one first you would end up calling an uninitialised variable. This error prevents that.

All you need to do is either define it before the switch statement or use curly braces { } to make sure it goes out of scope before exiting a specific case.

initialization of 'element' is skipped by 'case' label

2 Answers2