Handling errors from iterators

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With the reasoning that everything can be done with simple loops and if statements we'd never have any convenience methods at all :slight_smile: My intention was to use my own perceived difficulty at implementing faulty iterators as an example and find out if there were something that can be improved on the language/stdlib level.

I do concede my point that Rust needs a harder treatment for errors, based on the examples in this thread. However there are still two things left that I feel can be improved:

  • try! isn't usable inside next() — and I don't know what a good fix here might be for the general case. For now I'm content with my local variety of it.
  • There's no obvious iterator adaptor implementing the behaviour I'm after: yield an error and then stop. All suggested ways have slight warts on them, like take_while would swallow the error and fold_results and collect require O(n) storage… However! I won't press this point any further as I can't really present a good convincing example, even for myself. Probably this use-case is indeed an edge case.