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0 pointsakkad337mo ago0 comments

Is it expensive in Rust? Normally only data in stack gets copied. Heap data is untouched

0 comments

Yes, but if you have a large value type it will be on the stack unless you manually box it. Passing by value can get quite expensive quite fast, especially if the value keeps being passed up and down the call chain.

akkad33OP6mo ago

Is this really true? What do you mean by value types? The types that implement copy or any struct types? Because I think struct types only get moved

Tuna-Fish6mo ago

Move and copy are both the same operation under the hood, move just means that the old version is marked invalid and not available for use anymore.

For large structs (or enums), move and copy both compile into memcpy. If the structures are large, this can take a lot of time.

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