Trait InstanceIdentity

pub trait InstanceIdentity {
    // Required methods
    fn kind() -> &'static str;
    fn write_identity(&self, f: &mut Formatter<'_>) -> Result;
}

Available on crate feature state-dir only.

An instance of a facility that wants to save persistent state (caller-provided impl)

Each value of a type implementing InstanceIdentity designates a specific instance of a specific facility.

For example, HsNickname implements state_dir::InstanceIdentity.

The kind and identity are slugs.

Required Methods

fn kind() -> &'static str

Return the kind. For example hss for a Tor Hidden Service.

This must return a fixed string, since usually all instances represented the same Rust type are also the same kind.

The returned value must be valid as a slug.

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

Obtain identity

The instance identity distinguishes different instances of the same kind.

For example, for a Tor Hidden Service the identity is the nickname.

The generated string must be valid as a slug. If it is not, the functions in this module will throw Bug errors. (Returning fmt::Error will cause a panic, as is usual with the fmt API.)

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.

Implementors

impl InstanceIdentity for HsNickname