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CommandDispatcher

kaish_kernel::dispatch

Trait CommandDispatcher 

Source 
pub trait CommandDispatcher: Send + Sync {
    // Required methods
    fn dispatch<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        cmd: &'life1 Command,
        ctx: &'life2 mut ExecContext,
    ) -> Pin<Box<dyn Future<Output = Result<ExecResult>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait;
    fn eval_expr<'life0, 'life1, 'life2, 'async_trait>(
        &'life0 self,
        expr: &'life1 Expr,
        ctx: &'life2 ExecContext,
    ) -> Pin<Box<dyn Future<Output = Result<Value>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait,
             'life1: 'async_trait,
             'life2: 'async_trait;
    fn fork<'life0, 'async_trait>(
        &'life0 self,
    ) -> Pin<Box<dyn Future<Output = Arc<dyn CommandDispatcher>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait;

    // Provided method
    fn fork_attached<'life0, 'async_trait>(
        &'life0 self,
    ) -> Pin<Box<dyn Future<Output = Arc<dyn CommandDispatcher>> + Send + 'async_trait>>
       where Self: 'async_trait,
             'life0: 'async_trait { ... }
}
Expand description

Trait for dispatching a single command through the full resolution chain.

Implementations handle argument parsing, tool lookup, and execution. The pipeline runner handles I/O routing (stdin, redirects, piping).

Required Methods§

Source

fn dispatch<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, cmd: &'life1 Command, ctx: &'life2 mut ExecContext, ) -> Pin<Box<dyn Future<Output = Result<ExecResult>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Dispatch a single command for execution.

The ctx provides stdin (from pipe or redirect), scope, and backend. Implementations should handle schema-aware argument parsing and output format extraction internally.

Source

fn eval_expr<'life0, 'life1, 'life2, 'async_trait>( &'life0 self, expr: &'life1 Expr, ctx: &'life2 ExecContext, ) -> Pin<Box<dyn Future<Output = Result<Value>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait,

Evaluate an expression through the full async chain.

Unlike the runner’s sync eval_simple_expr, this can run command substitution ($(...)) because it has access to pipeline execution. Used for redirect targets and heredoc bodies so cat < $(cmd), echo x > $(cmd), and $(...) inside heredoc bodies work. The ctx carries scope/cwd/backend for dispatchers that evaluate against it; stateful dispatchers (Kernel) snapshot their own session state and only let command output escape (side effects like cd do not).

Source

fn fork<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Arc<dyn CommandDispatcher>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait,

Fork the dispatcher for concurrent execution (detached).

Returns a subsidiary dispatcher with independent mutable state, safe to run concurrently with the parent and other forks without data races on shared scope/cwd/aliases. Used by background & jobs, where the fork must survive parent cancellation.

For stateful dispatchers (e.g. Kernel) this snapshots per-session state into a fresh instance. Stateless dispatchers may clone.

Provided Methods§

Source

fn fork_attached<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Arc<dyn CommandDispatcher>> + Send + 'async_trait>>
where Self: 'async_trait, 'life0: 'async_trait,

Fork the dispatcher for concurrent execution (attached to parent cancel).

Like Self::fork but the fork’s cancellation token is a child of the parent’s. Cancelling the parent (timeout, Ctrl-C, embedder Kernel::cancel) cascades into the fork, which then kills its own external children via the usual SIGTERM/SIGKILL discipline.

Used for foreground concurrency: scatter workers, concurrent pipeline stages, command substitution. Default implementation delegates to Self::fork for stateless dispatchers that don’t track cancellation.

Dyn Compatibility§

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors§