diff options
Diffstat (limited to 'library/std/src/primitive_docs.rs')
| -rw-r--r-- | library/std/src/primitive_docs.rs | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/library/std/src/primitive_docs.rs b/library/std/src/primitive_docs.rs index 331714a993c..6f78811a186 100644 --- a/library/std/src/primitive_docs.rs +++ b/library/std/src/primitive_docs.rs @@ -587,8 +587,10 @@ mod prim_pointer {} /// There are two syntactic forms for creating an array: /// /// * A list with each element, i.e., `[x, y, z]`. -/// * A repeat expression `[x; N]`, which produces an array with `N` copies of `x`. -/// The type of `x` must be [`Copy`]. +/// * A repeat expression `[expr; N]` where `N` is how many times to repeat `expr` in the array. `expr` must either be: +/// +/// * A value of a type implementing the [`Copy`] trait +/// * A `const` value /// /// Note that `[expr; 0]` is allowed, and produces an empty array. /// This will still evaluate `expr`, however, and immediately drop the resulting value, so @@ -1493,11 +1495,13 @@ mod prim_ref {} /// However, a direct cast back is not possible. You need to use `transmute`: /// /// ```rust +/// # #[cfg(not(miri))] { // FIXME: use strict provenance APIs once they are stable, then remove this `cfg` /// # let fnptr: fn(i32) -> i32 = |x| x+2; /// # let fnptr_addr = fnptr as usize; /// let fnptr = fnptr_addr as *const (); /// let fnptr: fn(i32) -> i32 = unsafe { std::mem::transmute(fnptr) }; /// assert_eq!(fnptr(40), 42); +/// # } /// ``` /// /// Crucially, we `as`-cast to a raw pointer before `transmute`ing to a function pointer. |
