Initializing class members with {}

Question

Someone gave me (part of) the following code:

struct MyStruct
{
    int x = {};
    int y = {};

};

I never saw this syntax before, what does initialization with {} mean?

Answer 1

Since the C++11 standard there are two ways to initialize member variables:

1. Using the constructor initialization list as "usual":

   struct Foo
   {
       int x;
   
       Foo()
           : x(0)
       {
       }
   };
   

2. Use the new inline initialization where members are getting their "default" values using normal initialization syntax:

   struct Foo
   {
       int x = 0;
   };
   

Both these ways are for many values and types equivalent.