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Union types

A union type is a nominal, heterogeneous C-like union, denoted by the name of a union item.

A union access transmutes the content of the union to the type of the accessed field. Since transmutes can cause unexpected or undefined behaviour, unsafe is required to read from a union field or to write to a field that doesn't implement Copy.

The memory layout of a union is undefined by default, but the #[repr(...)] attribute can be used to fix a layout.

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Licensed under the Apache License, Version 2.0 or the MIT license, at your option.
https://doc.rust-lang.org/reference/types/union.html