Enum SizeHint 

pub enum SizeHint {
    None,
    Exact(u64),
    Unknown,
}

Size hint for type impl Body trait

Size is for Frame::Data variant only. Frame::Trailers is not inclued in hint

Variants

None

No sized. Body::poll_frame can be skipped entirely

Exact(u64)

Exact sized. Body::poll_frame can reliably expect all Frame::Data it can yield have a total byte length in exact number

Unknown

Unknown sized. Escape hatch when size can’t be reliably determined

Implementations

impl SizeHint

pub const NO_BODY_HINT: (usize, Option<usize>)

a crate hack for expressing SizeHint::None through Stream::size_hint

Trait Implementations

impl Add for SizeHint

type Output = SizeHint

The resulting type after applying the + operator.

fn add(self, rhs: SizeHint) -> <SizeHint as Add>::Output

Performs the + operation.

impl Clone for SizeHint

fn clone(&self) -> SizeHint

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for SizeHint

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

Formats the value using the given formatter.

impl Default for SizeHint

fn default() -> SizeHint

Returns the “default value” for a type.

impl PartialEq for SizeHint

fn eq(&self, other: &SizeHint) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Copy for SizeHint

impl Eq for SizeHint

impl StructuralPartialEq for SizeHint