Comment by verdagon

Unfortunately, Mojo kind of limits itself by forcing all parameters to be unique references or shared references. So the first example works in Mojo, but not the `step` example nor the `attack` example from the original group borrowing explanation. [0]

I hope they one day upgrade to full group borrowing, it would be a nice fit for them.

[0] https://verdagon.dev/blog/group-borrowing