Probably Dance

C++11 made the {} syntax for initializing aggregates more widely usable. You can now also use it to call constructors and to initialize with a std::initializer_list. It also allows you to drop the type name in some circumstances. The general recommendation seems to be that you use it as much as possible. But when I have started doing that I have found that it sometimes doesn’t do what I want, and that it may make maintenance more difficult.

Here’s what it looks like:

#include <iostream>

struct Widget
{
    Widget(int m) : m{m} {}
    operator int() const { return m; }
    int m;
};

Widget decrement_widget(Widget w)
{
    return { w - 1 };
}

int main()
{
    int a{1};
    std::cout << a << std::endl; // "1"
    Widget w{5};
    std::cout << w << std::endl; // "5"
    std::cout << decrement_widget({5}) << std::endl; // "4"
}

It can be used to initialize everything (hence the name uniform initialization) and as you can see it makes some code more convenient because I don’t even need the name any more if the compiler should know it.

It makes your code look a bit weird at first because you have squiggly braces everywhere, but after a while I found that I prefer it because it sets initialization apart from function calls.

But I have stopped using it and I recommend that you don’t use it either.

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