Initialize a constant sized array in an initializer list

Serge picture Serge · Aug 7, 2012 · Viewed 66.8k times · Source

I've got a situation which can be summarized in the following:

class Test
{

    Test();

    int MySet[10];

};

is it possible to initialize MySet in an initializer list?

Like this kind of initializer list:

Test::Test() : MySet({1, 2, 3, 4, 5, 6, 7, 8, 9, 10}) {}

Is there any way to initialize a constant-sized member array in a class's initalizer list?

Answer

obataku picture obataku · Aug 7, 2012

While not available in C++03, C++11 introduces extended initializer lists. You can indeed do it if using a compiler compliant with the C++11 standard.

struct Test {
    Test() : set { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 } { };
    int set[10];
};

The above code compiles fine using g++ -std=c++0x -c test.cc.


As pointed out below me by a helpful user in the comments, this code does not compile using Microsoft's VC++ compiler, cl. Perhaps someone can tell me if the equivalent using std::array will?

#include <array>

struct Test {
  Test() : set { { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 } } { };
  std::array<int, 10> set;
};

This also compiles fine using g++ -std=c++0x -c test.cc.