Hello, I am a n00b so pardon my ignorance. I am wondering why specifically non-primitive variables require me to use a reference (pointer - &) when assigning them as the value of another non-primitive variable. On the other hand, primitives can be assigned to, using just a simple '=' sign. Is this …

The confusion may also arise from the following difference (mem::drop is just an example "usage" of the value). This compiles fine: let arr1 = [1,2,3]; let arr2 = arr1; mem::drop(arr1); This compiles fine too (but would be an error in old versions, without NLL): let vec1 = vec![1,2,3]; let vec2 =…

[image] matveyryabov: I am wondering why specifically non-primitive variables require me to use a reference (pointer - &) when assigning them as the value of another non-primitive variable. On the other hand, primitives can be assigned to, using just a simple '=' sign. You can use = for both …

This is because a Copy will memcpy the data bit by bit, which is okay for primitives, given that they hold data which upon Dropping would not allow for a read-after-free: [[u | i][size | 8 | 16 | 32 | 64 | 128] | f[32 | 64] | char | bool] can all be literally represented by a number. Copying that…

Yes, it's essentially about whether they're on the heap or not in this case, although that's not necessarily the full picture. It's not really about if it's primitive, because you can implement very large structs which can be Copy. Everything from this section of the docs and below is good read: C…

Why do I need to use pointers for non-primitives (BEGINNER)

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matveyryabov July 22, 2019, 6:10pm 4

Is this due to their heap-allocated nature? Why do non-primitives require you to clone?

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Why do I need to use pointers for non-primitives (BEGINNER)

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