Diagrams

flowchart TB
    subgraph api["Public API"]
        variable["AsyncContext.Variable"]
        snapshot["AsyncContext.Snapshot"]
        als["AsyncLocalStorage"]
    end
    subgraph runtime["Runtime"]
        store["Store: the current frame"]
        frames["Frames: one variable and one value each"]
        coroutine["coroutine()"]
        bind["bindGenerator()"]
        patches["Patches: then, timers, events, observers, streams"]
    end
    als --> variable
    variable -->|"run() makes"| frames
    variable -->|"get() reads"| store
    snapshot -->|"records"| store
    coroutine -->|"sets for each step"| store
    bind -->|"sets for each step"| store
    patches -->|"sets for each callback"| store
    store --> frames

sequenceDiagram
    participant Caller
    participant Coroutine as coroutine()
    participant Body as Generator body
    participant Queue as Microtask queue
    Caller->>Coroutine: start the async function
    Coroutine->>Body: step 1 in the frame of the function
    Body-->>Coroutine: yield (was await)
    Coroutine->>Coroutine: set the previous frame
    Coroutine->>Queue: then() on the value
    Queue->>Coroutine: the value settles
    Coroutine->>Body: step 2 in the frame of the function
    Body-->>Coroutine: the function is complete
    Coroutine->>Coroutine: set the previous frame

flowchart TB
    module["Module (also in node_modules)"] --> plugin["Vite plugin, after the other plugins"]
    plugin --> bind["Bind the generators"]
    bind --> asyncgen["Async generators and for await"]
    asyncgen --> asyncfn["Async functions with coroutine()"]
    asyncfn --> out["Module that imports the runtime"]