Comment by verdagon

9 hours ago

Next article =) How the borrow checker handles ifs and loops is a pretty fun topic. If-statements work like you'd expect (invalidations from both branches are merged). Loops is where it gets weird: we have to scout all the invalidations that happen inside the loop and then "replay" them _before_ the body of the loop. I can explain it more if you'd like.

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verdagon

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user142  9 hours ago

I was wondering about the case where a reference points to a different path depending on control flow. I guess you can just design your language to make this impossible but this is still possible to do with pointers in C/C++.

  • verdagon  9 hours ago

    Theoretically, we can have a reference that points to two paths, a "path union" so to speak. If the user explicitly typed out the path union, it would be something like:

    let my_ref &Entity in (live_list[], dead_list[]) = if ...

    though it would be nicer in practice, because the compiler could infer that.

    Haven't implemented it yet of course, but the data structures in the borrow checker are designed with this in mind.