[rgovostes]

I was very confused by what the author is pointing out in the opening Point / Print example. ("[T]he compiler is allowed to convert that to a T" -> wait, why did the compiler change a struct to an int32?)

I think this boils down to: Carbon defaults to passing parameters that fit in a single register by value, and all others by const reference. This affects a few things you might take for granted in C++, like whether you can take a reference to a parameter.

The opening example is showing two samples of Carbon and the equivalent C++ code, noting that the "undecorated" parameter `p : Point` is equivalent to `const Point& p` (pass by const reference to a struct) and `x : i32` is equivalent to `std::int32_t x` (pass by value).

[mgaunard]

What's weird is that Point would fit in a register as well.