Struct Shared 

pub struct Shared(/* private fields */);

Available on crate features alloc or std only.

A strategy that preserves heap allocations for fast, zero-copy conversions with bytes::Bytes.

Overview

The Shared strategy prioritizes fast conversions and allocation sharing with bytes::Bytes. When data is heap-allocated, it remains on the heap even after operations like advance(), truncate(), or split_to/off() that reduce the size below the inline capacity.

This makes Shared ideal when:

• You frequently convert between Bytes and Bytes
• You want to share heap allocations (cheap clones via reference counting)
• Performance is more important than memory overhead

Behavior

• Inline → Inline: Inline source slices stay inline
• Heap → Heap: Every non-empty heap source slice stays shared and heap-allocated, even at or below the inline capacity; empty slices use the canonical empty value
• Conversions: Zero-cost From/Into with Bytes when heap-allocated

Example

use smol_bytes::shared::Bytes;
use bytes::Buf;

// Create heap-allocated bytes (>62 bytes)
let mut data = Bytes::from(vec![1u8; 100]);
assert!(data.is_heap());

// Advance past most data
data.advance(70); // Only 30 bytes remain

// Still heap-allocated! (Shared strategy preserves heap)
assert!(data.is_heap());

// Fast, zero-copy conversion to Bytes
let bytes: bytes::Bytes = data.into();
assert_eq!(bytes.len(), 30);

Comparison with Compact

Operation	Shared	Compact
Heap→Inline on shrink	❌ No	✅ Yes
Bytes conversion	⚡ Zero-copy	📋 May copy
Memory usage	💾 Higher	💾 Lower
Best for	Speed, Bytes interop	Memory efficiency

Trait Implementations

impl Clone for Shared

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for Shared

impl Debug for Shared

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

Formats the value using the given formatter.

impl Eq for Shared

impl Hash for Shared

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Shared

fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

fn clamp_to<R>(self, range: R) -> Self

where Self: Sized, R: ClampBounds<Self>,

🔬This is a nightly-only experimental API. (clamp_to)

Restrict a value to a certain range.

impl PartialEq for Shared

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

Equality operator ==.

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

Inequality operator !=.

impl PartialOrd for Shared

fn partial_cmp(&self, other: &Self) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

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

Tests less than (for self and other) and is used by the < operator.

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

Tests less than or equal to (for self and other) and is used by the <= operator.

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

Tests greater than (for self and other) and is used by the > operator.

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

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for Shared