Trait Discriminator

pub trait Discriminator {
    const DISCRIMINATOR: &'static [u8];
}

Unique identifier for a type.

This is not a trait you should derive manually, as various Anchor macros already derive it internally.

Prior to Anchor v0.31, discriminators were always 8 bytes in size. However, starting with Anchor v0.31, it is possible to override the default discriminators, and discriminator length is no longer fixed, which means this trait can also be implemented for non-Anchor programs.

It’s important that the discriminator is always unique for the type you’re implementing it for. While the discriminator can be at any length (including zero), the IDL generation does not currently allow empty discriminators for safety and convenience reasons. However, the trait definition still allows empty discriminators because some non-Anchor programs, e.g. the SPL Token program, don’t have account discriminators. In that case, safety checks should never depend on the discriminator.

Required Associated Constants

const DISCRIMINATOR: &'static [u8]

Discriminator slice.

See Discriminator trait documentation for more information.

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl Discriminator for Destroy

const DISCRIMINATOR: &'static [u8]

impl Discriminator for Initialize

const DISCRIMINATOR: &'static [u8]

impl Discriminator for Update

const DISCRIMINATOR: &'static [u8]

impl Discriminator for UpdateWithSession

const DISCRIMINATOR: &'static [u8]

impl Discriminator for BoltExecute

const DISCRIMINATOR: &'static [u8]

impl Discriminator for CreateSession

const DISCRIMINATOR: &'static [u8]

impl Discriminator for RevokeSession

const DISCRIMINATOR: &'static [u8]

impl Discriminator for SessionToken

const DISCRIMINATOR: &'static [u8]

impl Discriminator for AddAuthority

const DISCRIMINATOR: &'static [u8]

impl Discriminator for AddEntity

const DISCRIMINATOR: &'static [u8]

impl Discriminator for Apply

const DISCRIMINATOR: &'static [u8]

impl Discriminator for ApplyWithSession

const DISCRIMINATOR: &'static [u8]

impl Discriminator for ApproveSystem

const DISCRIMINATOR: &'static [u8]

impl Discriminator for DestroyComponent

const DISCRIMINATOR: &'static [u8]

impl Discriminator for InitializeComponent

const DISCRIMINATOR: &'static [u8]

impl Discriminator for InitializeNewWorld

const DISCRIMINATOR: &'static [u8]

impl Discriminator for InitializeRegistry

const DISCRIMINATOR: &'static [u8]

impl Discriminator for RemoveAuthority

const DISCRIMINATOR: &'static [u8]

impl Discriminator for RemoveSystem

const DISCRIMINATOR: &'static [u8]

impl Discriminator for Registry

const DISCRIMINATOR: &'static [u8]

impl Discriminator for SystemWhitelist

const DISCRIMINATOR: &'static [u8]

impl Discriminator for World

const DISCRIMINATOR: &'static [u8]

Implementors

impl Discriminator for Entity

const DISCRIMINATOR: &'static [u8]