Struct EphemeralValue 

pub struct EphemeralValue<T> { /* private fields */ }

A channel that is cleared after each superstep.

Ephemeral channels are useful for temporary data that should only be visible to nodes within a single superstep. After the step completes, the value is automatically cleared.

Example

use rust_langgraph::channels::{BaseChannel, EphemeralValue};

let mut channel = EphemeralValue::<String>::new();
channel.update(vec![serde_json::json!("temporary")]).unwrap();
assert!(channel.get().unwrap().is_some());

// After superstep (simulated by calling clear)
channel.clear();
assert!(channel.get().unwrap().is_none());

Implementations

impl<T> EphemeralValue<T>

pub fn new() -> Self

Create a new empty EphemeralValue channel

pub fn clear(&mut self)

Clear the ephemeral value

Trait Implementations

impl<T> BaseChannel for EphemeralValue<T>

where T: Serialize + for<'de> Deserialize<'de> + Clone + Send + Sync + Debug + 'static,

fn get(&self) -> Result<Option<Value>>

Get the current value as JSON

fn update(&mut self, values: Vec<Value>) -> Result<()>

Update the channel with new values

fn checkpoint(&self) -> Result<Value>

Serialize the channel state for checkpointing

fn from_checkpoint(_data: Value) -> Result<Box<dyn BaseChannel>>

Restore the channel state from a checkpoint

fn type_name(&self) -> &'static str

Get the channel’s type name for debugging

fn is_empty(&self) -> bool

Check if the channel is empty

impl<T: Clone> Clone for EphemeralValue<T>

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

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<T: Debug> Debug for EphemeralValue<T>

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

Formats the value using the given formatter.

impl<T> Default for EphemeralValue<T>

fn default() -> Self

Returns the “default value” for a type.