Why we don't use the NEW word?

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#1

In C#, in order to instantiate a class we use the ‘new’ keyword.

In C++ why don’t we make the same?
It fells strange to simply put a

FBullCowGame BCGame;

is just like saying

int someinteger;

and expect to respond to a value.

#2

Because new would make a heap allocation and return you a pointer to that memory address where it was allocated. Doing FBullCowGame BCGame; implicitly calls the default constructor which should initialise the data members of the class on the stack.

#3

I have a related question: Does not using “new” still create a FBullCowGame object (In C#, doing so would result in a “null” variable)? And if so, doesn’t mean that it allocate memory anyway for that object? I’m not really sure that I understand what you mean by “a heap allocation”.

Also, could our constructor take parameters and, if so, wouldn’t force us to use “new”?

#4

Yes.

class FBullCowGame
{
    int MyMaxTries = 5;
    int MyCurrentTry = 1;
};

int main()
{
    FBullCowGame BCGame; //BCGame.MyCurrentTry = 1, BCGame.MyMaxTries = 5
}

Note that this is different for the built-in types as they don’t have constructors so int MyInt; is an uninitalised variable

Yes but it allocates it on the stack. Further reading: https://stackoverflow.com/questions/79923/what-and-where-are-the-stack-and-heap

Yes it can and no, new still doesn’t need to be used.

class FBullCowGame
{
public:
    FBullCowGame(int CurrentTry, int MaxTries) : MyCurrentTry(CurrentTry), MyMaxTries(MaxTries) {}
private:
    int MyMaxTries = 5;
    int MyCurrentTry = 1;
};

int main()
{
    FBullCowGame BCGame(10, 20); //BCGame.MyCurrentTry = 10, BCGame.MyMaxTries = 20
}

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