C++ Private structure and non static const variables initialization

Question

I totally disappointed. I have class, there I have private structure. And what's the silly problem: I just can't preinitialize some variables!
What I mean:
I need:

struct someStruct
    {
        someStruct *next = NULL;
        int number;
    };

I just want to create easy dynamic list, adding new elements from heap.
And what I should do?

struct someStruct
    {
        someStruct *next;
        int number;
    };

Put

someStruct *newElement = new someStruct;
newElement.next = NULL;

every time? I can forget about this.
Please help me. Because it's not a problem when I need to add 1 useless string. But what if I have 50 default variables?

http://stackoverflow.com/questions/3102096/when-do-c-pod-types-get-zero-initialized — Mat, Aug 10 '13 at 14:16

score 2 · Accepted Answer · edited May 23 '17 at 12:20

2

You cannot initialize class members when you declare them. Instead, you need a constructor:

struct someStruct {
    someStruct(): next(NULL), number(0) {}
    someStruct *next;
    int number;
};

Alternatively, for POD (plain old data), you could use your original class with no constructors and use someStruct *newElement = new someStruct(); to create a someStruct. This initializes the members to zero.

Also, C++11 supports in-class member initializers.

edited May 23 '17 at 12:20

Community

1
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answered Aug 10 '13 at 14:14

Yang

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Alternatively, initialize a the point of declaration in C++11. – juanchopanza Aug 10 '13 at 14:18
Alternative 2: `someStruct *newElement = new someStrsomeStruct();`, requires no modification to the original class. – juanchopanza Aug 10 '13 at 14:25
@Destiner You can find a list of supported C++11 features at http://msdn.microsoft.com/en-us/library/vstudio/hh567368.aspx. Currently, Non-static data member initializers aren't supported. – Yang Aug 10 '13 at 15:01

C++ Private structure and non static const variables initialization

1 Answers1