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library/std/src/keyword_docs.rs

@@ -1992,6 +1992,7 @@ mod type_keyword {}
 /// ```rust
 /// # #![allow(dead_code)]
 /// #![deny(unsafe_op_in_unsafe_fn)]
+///
 /// /// Dereference the given pointer.
 /// ///
 /// /// # Safety
@@ -2115,11 +2116,11 @@ mod type_keyword {}
 /// is not implicitly an unsafe block.) For that purpose it can make use of the contract that all
 /// its callers must uphold -- the fact that `idx < LEN`.
 ///
-/// Formally speaking, an `unsafe fn` in a trait is a function with extra
+/// Formally speaking, an `unsafe fn` in a trait is a function with *preconditions* that go beyond
-/// *preconditions* (such as `idx < LEN`), whereas an `unsafe trait` can declare
+/// those encoded by the argument types (such as `idx < LEN`), whereas an `unsafe trait` can declare
-/// that some of its functions have extra *postconditions* (such as returning an
+/// that some of its functions have *postconditions* that go beyond those encoded in the return type
-/// even integer). If a trait needs a function with both extra precondition and
+/// (such as returning an even integer). If a trait needs a function with both extra precondition
-/// extra postcondition, then it needs an `unsafe fn` in an `unsafe trait`.
+/// and extra postcondition, then it needs an `unsafe fn` in an `unsafe trait`.
 ///
 /// [`extern`]: keyword.extern.html
 /// [`trait`]: keyword.trait.html