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safety contract

The conditions a caller must guarantee before calling an unsafe function.

An unsafe fn documents its preconditions in a # Safety section; each unsafe block states in a // SAFETY: comment why those conditions hold at that call.

Examples

  • A /// # Safety doc section saying i must be less than stacks.len() is the contract; Clippy's missing_safety_doc flags a pub unsafe fn without one.

See also

unsafe block soundness doc comment
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