[Measter]

So in Rust an unsafe block and an unsafe function mean two different things. An unsafe block allows you to do things that are unsafe, such as dereference raw pointers, access union fields, calling unsafe functions, etc.

Unsafe functions mark that the caller is responsible for upholding the invariants necessary to avoid UB. In the 2021 and earlier editions, they also implicitly created an unsafe block in the body, but don't in 2024.

Or, in a more pithy tone: an unsafe block is the "hold my beer" block, while an unsafe function is a "put down your beer" function.