Enum BatchView 

pub enum BatchView<'a, I> {
    Owned(Vec<I>),
    Borrowed(&'a mut [I], usize),
}

An internal batch container used by the runtime/nodelink/stepcontext.

Generic over the stored item I. Commonly I = Message<P>, but by using a stored-item generic the same type works for any Edge whose Item is a Payload-implementing type.

• Owned(Vec<I>): when alloc feature is enabled and we can own a Vec.
• Borrowed(&'a mut [I], len): stack/heapless-backed buffer with explicit length.

Variants

Owned(Vec<I>)

Owned variant (alloc-enabled). Stores the entire Vec<I>.

Borrowed(&'a mut [I], usize)

Borrowed variant: a mutable slice plus a length indicating the valid prefix.

Implementations

impl<'a, I> BatchView<'a, I>

pub fn from_owned(v: Vec<I>) -> Self

Construct from an owned Vec (alloc feature required).

pub fn from_borrowed(buf: &'a mut [I], len: usize) -> Self

Construct from a borrowed slice + length.

pub fn len(&self) -> usize

Number of items in the batch.

pub fn is_empty(&self) -> bool

Is the batch empty?

pub fn iter(&self) -> Iter<'_, I>

Immutable iterator over items.

pub fn iter_mut(&mut self) -> IterMut<'_, I>

Mutable iterator over items.

pub fn as_slice(&self) -> &[I]

Return an immutable slice over the valid items.

impl<'a, P: Payload> BatchView<'a, Message<P>>

Special-case helpers for the common stored-item type: Message<P>.

pub fn as_batch(&self) -> Batch<'_, P>

Convert to the public, borrowed Batch<'_, P> view.

This is only available when the stored item is Message<P>.

pub fn first_header_mut(&mut self) -> Option<&mut MessageHeader>

Mutable access to the first message header if present.

pub fn last_header_mut(&mut self) -> Option<&mut MessageHeader>

Mutable access to the last message header if present.

pub fn into_batch_ref(&self) -> Batch<'_, P>

Try to convert into a borrowed Batch<'_, P> while keeping self alive. Equivalent to self.as_batch() but offered for clarity.

pub fn into_owned<'b>(self) -> BatchView<'b, Message<P>>

where Message<P>: Clone,

Convert this batch view into an owned batch view.

This is required by mutex-backed edges: a borrowed batch cannot escape the lock guard.

Semantics:

• If already Owned, the inner Vec is forwarded.
• If Borrowed, the valid prefix is cloned into a new Vec.

The returned BatchView is Owned and does not borrow from the original 'a.

pub fn into_vec(self) -> Vec<Message<P>>

where P: Clone,

Consume and return an owned Vec<Message<P>>.

• If this BatchView is Owned, returns the inner Vec without copying.
• If this BatchView is Borrowed, clones the valid prefix into a new Vec.

Alloc-only.

Trait Implementations

impl<'a, I: Debug> Debug for BatchView<'a, I>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<'a, P: Payload> Payload for &'a BatchView<'a, Message<P>>

fn buffer_descriptor(&self) -> BufferDescriptor

Return a descriptor containing the byte size of this payload.

impl<'a, P: Payload> Payload for BatchView<'a, Message<P>>

fn buffer_descriptor(&self) -> BufferDescriptor

Return a descriptor containing the byte size of this payload.