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Why the unsafe keyword exists

• Rust ensures safety
• But there are limits to what the compiler can do
• The unsafe keyword allows programmers to assume responsibility for Rust’s rules

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“A fundamental goal of Rust is to ensure memory safety.”

“But, there are limits. Some safety considerations cannot be expressed in a programming language. Even if they could be, there are limits to what the Rust compiler can control.”

“The unsafe keyword shifts the burden of upholding Rust’s rules from the compiler to the programmer.”

“When you see the unsafe keyword, you are seeing responsibility shift from the compiler to the programmer.

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