Struct heph::actor::SyncContext

pub struct SyncContext<M, RT> { /* private fields */ }

The context in which a synchronous actor is executed.

This context can be used for a number of things including receiving messages.

Implementations

impl<M, RT> SyncContext<M, RT>

pub fn try_receive_next(&mut self) -> Result<M, RecvError>

Attempt to receive the next message.

This will attempt to receive the next message if one is available. If the actor wants to wait until a message is received receive_next can be used, which blocks until a message is ready.

Examples

A synchronous actor that receives a name to greet, or greets the entire world.

use heph::actor::SyncContext;

fn greeter_actor<RT>(mut ctx: SyncContext<String, RT>) {
    if let Ok(name) = ctx.try_receive_next() {
        println!("Hello {}", name);
    } else {
        println!("Hello world");
    }
}

pub fn receive_next(&mut self) -> Result<M, NoMessages>

Receive the next message.

Returns the next message available. If no messages are currently available it will block until a message becomes available or until all actor references (that reference this actor) are dropped.

Examples

An actor that waits for a message and prints it.

use heph::actor::SyncContext;

fn print_actor<RT>(mut ctx: SyncContext<String, RT>) {
    if let Ok(msg) = ctx.receive_next() {
        println!("Got a message: {}", msg);
    } else {
        eprintln!("No message received");
    }
}

pub fn block_on<Fut>(&mut self, fut: Fut) -> Fut::Output where
    Fut: Future, 

Block on a Future waiting for it’s completion.

Limitations

Any Future returned by a type that is bound to an actor (see Bound trait of the heph-rt crate) cannot be used by this function. Those types use specialised wake-up mechanisms bypassing the Future’s task system.

pub fn runtime(&mut self) -> &mut RT

Get mutable access to the runtime this actor is running in.

pub const fn runtime_ref(&self) -> &RT

Get access to the runtime this actor is running in.

Trait Implementations

impl<M: Debug, RT: Debug> Debug for SyncContext<M, RT>

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

Formats the value using the given formatter.