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Hands-on Rust: why a second clone?

mikecargal

mikecargal

Hands-on Rust: why a second clone?

Title: Hands-On Rust (Chapter 10: Iterating Away the Chaos)

in the iteration function, why is it necessary to return a clone of new_tiles (which was already cloned from map.tiles?)

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herbert

herbert

Author of Hands-on Rust

I have a build (I wish I had room to include it in the book) that plays itself over and over. After a few hours, no errors with the clone omitted - so it’ll be trimmed for the next beta. Thanks! :slight_smile:

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mikecargal

mikecargal

Yeah, I skipped it, and now that I have things wired up it seems to work fine. Guess I’ll let you know if I stumble across some issue.

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herbert

herbert

Author of Hands-on Rust

That’s actually a very good question. It appears to work fine without it (it replaces the copy with a move; both compile down to memcpy so it winds up not making a lot of difference in terms of performance). My notes indicate that I had problems with an earlier Rust compiler there, so I’m going to test the heck out of it before committing the change. Thanks!

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