diff options
| -rw-r--r-- | library/alloc/src/vec/mod.rs | 21 |
1 files changed, 21 insertions, 0 deletions
diff --git a/library/alloc/src/vec/mod.rs b/library/alloc/src/vec/mod.rs index ccc4f03a1e5..88cdf588e35 100644 --- a/library/alloc/src/vec/mod.rs +++ b/library/alloc/src/vec/mod.rs @@ -253,6 +253,26 @@ mod spec_extend; /// can be slow. For this reason, it is recommended to use [`Vec::with_capacity`] /// whenever possible to specify how big the vector is expected to get. /// +/// A vector containing the elements `'a'` and `'b'` with capacity 4 can be +/// visualized as: +/// +/// ```text +/// Stack ptr len capacity +/// /Heap +--------+--------+--------+ +/// | 0x0123 | 2 | 4 | +/// +--------+--------+--------+ +/// | +/// v +/// Heap +--------+--------+--------+--------+ +/// | 'a' | 'b' | uninit | uninit | +/// +--------+--------+--------+--------+ +/// ``` +/// +/// - **uninit** represents memory that is not initialized, see [`MaybeUninit`]. +/// - Note: the ABI is not stable and `Vec` makes no guarantees about its memory +/// layout (including the order of fields). See [the section about +/// guarantees](#guarantees). +/// /// # Guarantees /// /// Due to its incredibly fundamental nature, `Vec` makes a lot of guarantees @@ -345,6 +365,7 @@ mod spec_extend; /// [`push`]: Vec::push /// [`insert`]: Vec::insert /// [`reserve`]: Vec::reserve +/// [`MaybeUninit`]: core::mem::MaybeUninit /// [owned slice]: Box /// [slice]: ../../std/primitive.slice.html /// [`&`]: ../../std/primitive.reference.html |