Initialize a large, fixed-size array with non-Copy types

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You could use the Default trait to initialize the array with default values:

let array: [Option<Box<Thing>>; SIZE] = Default::default();

See this playground for a working example.

Note that this will only work for arrays with up to 32 elements, because Default::default is only implemented for up to [T; 32]. See https://doc.rust-lang.org/std/default/trait.Default.html#impl-Default-98

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