Struct BranchToken 

pub struct BranchToken<T, S: BranchState> {
    pub _task: PhantomData<T>,
    pub _state: PhantomData<S>,
}

An ownership-bearing token representing a specific execution path. Since _task and _state are PhantomData, this struct has a size of 0 bytes.

Representation

A zero-sized type BranchToken holding a PhantomData<T> and PhantomData<S>. Its size in memory is 0 bytes.

Structure-only

Models compile-time ownership of an abstract execution path. It holds no runtime task references, performs no execution, and does not schedule workloads.

Graduation

In wasm4pm, a token represents a dynamic work item tracked by the runtime database. In the compat library, it enforces compile-time sequencing and typestate safety.

Fields

_task: PhantomData<T>

_state: PhantomData<S>

Implementations

impl<T> BranchToken<T, Pending>

pub fn start(self) -> BranchToken<T, Running>

Progresses the branch from Pending to Running.

Examples

use wasm4pm_compat::workflow::{BranchToken, Pending, Running};
use std::marker::PhantomData;

struct MyTask;
let token: BranchToken<MyTask, Pending> = BranchToken {
    _task: PhantomData,
    _state: PhantomData,
};
let running_token: BranchToken<MyTask, Running> = token.start();

impl<T> BranchToken<T, Running>

pub fn complete(self) -> BranchToken<T, Completed>

Normal successful completion of the branch.

Examples

use wasm4pm_compat::workflow::{BranchToken, Running, Completed};
use std::marker::PhantomData;

struct MyTask;
let token: BranchToken<MyTask, Running> = BranchToken {
    _task: PhantomData,
    _state: PhantomData,
};
let completed_token: BranchToken<MyTask, Completed> = token.complete();