How to delete a variable.

[brandonator]

I was wondering if someone could tell me how to delete a variable so if i say wanted to no longer use it, or after its deleted declare it as an int, or double ect; i could do it with the same variable.

/* the following code works in my full
program, however with the delete
command it does not, and i am
trying to delete "string x" */

void Player1()
{
Player Player1;

string x;

cout << "What is your name? ";
cin >> x;
Player1.SetPlayerName(x);

cout << "What is your age? ";
cin >> x;
Player1.SetPlayerAge(x);

cout << "What is your gender? ";
cin >> x;
Player1.SetPlayerGender(x);

delete x;
}

[ModShop]

The delete keyword can only be used with dynamically allocated memory (that is, memory obtained by using the new keyword). You have several options in this case:

1. Dynamically allocate/de-allocate X (bad):

string* x = new string();
//...
delete x;

2. clear() the content of X to free memory (good):

string x;
//...
x.clear();

3. Put X in a lower scope so that it goes away when that scope ends (good):

//in main
{
    string x;
    //...
    //copy X into player
} //x is destroyed here 

[AbstractionAnon]

There's is no reason to delete x, since x goes out of scope and is deleted from the stack automatically when your function exits.

BTW, it's not a very good idea to name your variables the same as your function name.

[brandonator]

what if i wanted to do this? in this example how would i do this with just "x"

void Player1()
{
Player Player1;

string x;

cout << "What is your name? ";
cin >> x;
Player1.SetPlayerName(x);

cout << "What is your age? ";
int x; // notice int instead of string
cin >> x;
Player1.SetPlayerAge(x);

cout << "What is your gender? ";
cin >> x;
Player1.SetPlayerGender(x);

delete x;
}

283 C:\Dev-Cpp\Untitled10.cpp conflicting declaration 'int x'

thats the error code it would come up with

[Moeljbcp]

Sorry, you'll just have to declare more than one variable. It helps prevent ambiguity anyway, there is no reason why you should ever want nor need to do what you just described.

e: If you really want to have a data type that can hold either an int or a string declare a union that can hold either an int or a string I guess. But seriously don't do this unless there's some logical reason why a variable could hold either an int or a string.

[AbstractionAnon]

Name them differently. No reason the int has to be named x also.

Names such as string s; and int i; instead of x help remind you of the type of the variable. Note that at line 18, setPlayerGender probably is not expectig an int.

[Chervil]

You could use braces to limit scope, the first example gives a compiler error

    string x = "abc";
    cout << x << endl;
    int x = 123;
    cout << x << endl;

but this compiles ok. Though it's not necessarily a good idea...

    {
        string x = "abc";
        cout << x << endl;
    }

    {
        int x = 123;
        cout << x << endl;
    }