Struct Tags 

pub struct Tags { /* private fields */ }

A lightweight, sorted collection of key-value string tags.

Tags are stored in a SmallVec with inline capacity for up to 16 entries, avoiding heap allocation for typical use cases. Keys are kept sorted for efficient binary search lookup.

Both keys and values use SmolStr for small string optimization, providing zero-allocation storage for strings ≤22 bytes.

Example

let mut tags = Tags::new();
tags.set("env", "prod");
tags.set("region", "us-west");

assert_eq!(tags.get("env"), Some("prod"));
assert!(tags.contains_key("region"));

Implementations

impl Tags

pub fn new() -> Self

Create a new empty Tags collection.

pub fn set(&mut self, key: impl Into<SmolStr>, value: impl Into<SmolStr>)

Set a tag value. If the key exists, the value is updated.

Keys are kept sorted for efficient lookup.

pub fn get(&self, key: &str) -> Option<&str>

Get a tag value by key.

Returns None if the key doesn’t exist.

pub fn contains_key(&self, key: &str) -> bool

Check if a key exists in the tags.

pub fn remove(&mut self, key: &str) -> Option<SmolStr>

Remove a tag by key.

Returns the removed value if the key existed.

pub fn is_empty(&self) -> bool

Check if the collection is empty.

pub fn len(&self) -> usize

Return the number of tags.

pub fn iter(&self) -> impl Iterator<Item = (&str, &str)>

Iterate over all key-value pairs.

pub fn keys(&self) -> impl Iterator<Item = &str>

Iterate over all keys.

pub fn values(&self) -> impl Iterator<Item = &str>

Iterate over all values.

pub fn clear(&mut self)

Clear all tags.

impl Tags

pub fn set_tag(&mut self, key: &str, value: String)

👎Deprecated since 0.6.0: Use set() instead

Set a tag value.

Trait Implementations

impl Clone for Tags

fn clone(&self) -> Tags

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Tags

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

Formats the value using the given formatter.

impl Default for Tags

fn default() -> Tags

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Tags

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for Tags

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.