Really confusing behavior of type inference with `consuming`

[taylorswift]

@Nobody1707

I was under the impression that consuming was the official version of __owned, and that being able to directly mutate the parameter was the only real difference between the unstable feature and the stable one. I had expected all the implicilty __owned parameters to act as consuming in compilers that support ownership since the lack of mutablity is a purely artificial constraint and not affected by ABI. It's really weird that they don't.

__owned is solely about ARC convention, an __owned parameter still lives for the entire duration of the function’s execution, so if you mutate it inside the function it will always copy since the parameter itself is immutable and cannot be eagerly moved into something mutable.