Function gstd::msg::send

source · 
pub fn send<E: Encode>(
    program: ActorId,
    payload: E,
    value: u128,
) -> Result<MessageId>
Expand description

Send a new message to the program or user.

Gear allows programs to communicate with each other and users via messages. For example, the send function allows sending such messages.

The first argument is the address of the target account (ActorId). The second argument is the encodable payload. The last argument is the value to be transferred from the current program account to the message target account.

Send transaction will be posted after processing is finished, similar to the reply message reply.

§Examples

Send a message to the arbitrary address:

use gstd::{msg, prelude::*, ActorId};

#[derive(Encode)]
#[codec(crate = gstd::codec)]
struct Output {
    a: i32,
    b: Option<bool>,
}

#[no_mangle]
extern "C" fn handle() {
    let payload = Output {
        a: 42,
        b: Some(true),
    };

    // Receiver id is collected from bytes from 0 to 31
    let id: [u8; 32] = core::array::from_fn(|i| i as u8);
    msg::send(ActorId::new(id), payload, 0).expect("Unable to send");
}

§See also