What's the meaning of this C++ syntax

Question

I found this c++ code but I can't understand this syntax:

auto path_dbus = [&](DBus::Connection &bus) {
    ...
};

Answer 1

It is a lambda function that:

• captures any used variables by reference [&]
• takes an argument (DBus::Connection&)
• does some work {...}

To break down that line:

auto path_dbus = [&]      (DBus::Connection &bus) {... };
                 ^capture ^arguments              ^work