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[Rust] Lifetime of Reference in HashMap
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| struct Cheese<K1, K2, V> { | |
| things: HashMap<K1, V>, | |
| refs: HashMap<K2, &V> | |
| } |
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KrishnaSannasi:
You can't, Rust dislikes self referential types like this, and there is no syntax to safely create them. (Actually, you can make a self referential type with safe Rust, it's just almost useless)
Even if you try and use unsafe, you can't soundly do this because HashMap reallocates on resizes, and this would invalidate all pointers into it.
More detail: https://users.rust-lang.org/t/lifetimes-of-references-in-hashmaps/33942