Trait FixedBitLen 

pub trait FixedBitLen {
    const BIT_LEN: u32;
}

A message whose encoded length is a compile-time constant — i.e. it has no variable-length (count-driven Vec) field. The derive implements this only for fixed messages; it sizes a fixed byte region when the message is embedded as a field in another message (its contribution to the parent’s width). A count-bearing message implements BitDecode/BitEncode but not this. Bits leaves also implement it (their BIT_LEN is Bits::BITS), so a field’s width is computed uniformly whether it’s a leaf or a nested message.

Required Associated Constants

const BIT_LEN: u32

Total encoded width of the message in bits — the sum of its fields’ widths.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementations on Foreign Types

impl FixedBitLen for Ipv4Addr

Available on crate feature std only.

const BIT_LEN: u32 = 32

impl FixedBitLen for Ipv6Addr

Available on crate feature std only.

const BIT_LEN: u32 = 128

impl FixedBitLen for bool

const BIT_LEN: u32 = <bool as Bits>::BITS

impl FixedBitLen for u8

const BIT_LEN: u32 = <u8 as Bits>::BITS

impl FixedBitLen for u16

const BIT_LEN: u32 = <u16 as Bits>::BITS

impl FixedBitLen for u32

const BIT_LEN: u32 = <u32 as Bits>::BITS

impl FixedBitLen for u64

const BIT_LEN: u32 = <u64 as Bits>::BITS

impl FixedBitLen for u128

const BIT_LEN: u32 = <u128 as Bits>::BITS

Implementors

impl<T, const N: usize> FixedBitLen for UInt<T, N>

where UInt<T, N>: Bits,

const BIT_LEN: u32 = <Self as Bits>::BITS

impl<T: Bits> FixedBitLen for WireLen<T>

A WireLen<T> occupies exactly T’s width, so it stays a fixed-width field (a DNS header with WireLen<u16> counts is still 12 bytes).

const BIT_LEN: u32 = <T as Bits>::BITS