When reading the chapter Using Box to Point to Data on the Heap from the rust book, it says: Boxes don’t have performance overhead, other than storing their data on the heap instead of on the stack. But they don’t have many extra capabilities either. You’ll use them most often in these situations: …

[image] not-rusty: Which kinds of context is necessary to know the size of the type? Why does it need to know it? In order to be able to find things like parameters or struct items efficiently, rust needs them to have fixed sizes, so they are at fixed offsets in memory ( some things can be pl…

Why does rust need to know the size of types at compile time?

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H2CO3 November 14, 2021, 4:13pm 2

Any time you want to copy (or move) it, for example. This includes returning something by value.

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Why does rust need to know the size of types at compile time?

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