Struct zng::event::CommandMetaVarId

pub struct CommandMetaVarId<T>(/* private fields */)
where
    T: StateValue + VarValue;

Unique identifier of a command metadata state variable.

This type is very similar to StateId, but T is the value type of the metadata variable.

Memory

The internal number is a NonZeroU64, that means that Option<CommandMetaVarId> and CommandMetaVarId are the same size as u64.

As Hash

The generated internal number has good statistical distribution and can be used as its own hash, although it is not cryptographically safe, as it is simply a sequential counter scrambled using splitmix64.

Static

The unique ID cannot be generated at compile time, but you can use the static_id! macro to declare a lazy static that instantiates the ID.

Implementations

impl<T> CommandMetaVarId<T>

where T: StateValue + VarValue,

pub fn new_unique() -> CommandMetaVarId<T>

Generates a new unique ID.

pub fn get(self) -> u64

Retrieve the underlying value.

pub fn sequential(self) -> u64

Un-scramble the underlying value to get the original sequential count number.

If two IDs, id0 and id1 where generated by the same thread then id0.sequential() < id1.sequential().

pub fn from_raw(raw: u64) -> CommandMetaVarId<T>

Creates an ID from a raw value.

The value must not be zero, panics if it is, the value must have been provided by get otherwise the ID will not be unique.

pub fn from_sequential(num: u64) -> CommandMetaVarId<T>

Creates an ID from a sequential number.

Safety

The value must not be zero, panics if it is, the value must have been provided by sequential otherwise the ID will not be unique.

Trait Implementations

impl<T> Clone for CommandMetaVarId<T>

where T: StateValue + VarValue,

fn clone(&self) -> CommandMetaVarId<T>

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T> Debug for CommandMetaVarId<T>

where T: StateValue + VarValue,

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

Formats the value using the given formatter.

impl<T> Hash for CommandMetaVarId<T>

where T: StateValue + VarValue,

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

where H: Hasher,

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<T> PartialEq for CommandMetaVarId<T>

where T: StateValue + VarValue,

fn eq(&self, other: &CommandMetaVarId<T>) -> 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<T> UniqueId for CommandMetaVarId<T>

where T: StateValue + VarValue,

fn new_unique() -> CommandMetaVarId<T>

New unique ID.

impl<T> Copy for CommandMetaVarId<T>

where T: StateValue + VarValue,

impl<T> Eq for CommandMetaVarId<T>

where T: StateValue + VarValue,

impl<T> NoUninit for CommandMetaVarId<T>

where T: StateValue + VarValue,

impl<T> PodInOption for CommandMetaVarId<T>

where T: StateValue + VarValue,

impl<T> ZeroableInOption for CommandMetaVarId<T>

where T: StateValue + VarValue,