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I have not used Rust before; does working with statistical analysis of runtime environments hinder debugging? In a multithreaded environment - does it pause the world for its runtime analysis or are there locks on shared resources representing ownership of individual objects, or does it do copies on writes of resources for idempotent operations as the references are moved around environment for lockless operations?

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> does it pause the world for its runtime analysis

The borrow checker is _entirely_ at compile time.

To be fair, resource disposal is sometimes "delegated" to runtime. But it's always a local concern, like a reference counter for a shared resource, or a mutable `Option<R>` value that can have the R resource taken out of it or put back into it dynamically. There's no creepy overarching runtime system that tracks individual objects from a distance.

Yes, it's hard to figure out which way to talk about it. Rc<T> isn't really part of the borrow checker... it technically subverts it to do its own thing internally.

I wouldn't really consider the whole ownership thing or specifically the mechanism that inserts destructor calls at the logical end of a value's lifetime part of the borrow checker either, but I dunno how the implementation is laid out.

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