waitUntil

Wait for a bloc's state to meet a condition. Automatically tracks dependencies accessed in the predicate.

Basic Usage

Wait for a condition on the bloc, returns the bloc instance:

import { waitUntil } from '@blac/core';

const userBloc = await waitUntil(
  UserBloc,
  (bloc) => bloc.state.isAuthenticated,
);
// userBloc is now authenticated

With Selector

Wait for a condition on a selected value, returns the selected value:

const layout = await waitUntil(
  LayoutBloc,
  (bloc) => bloc.state.currentLayout, // selector
  (layout) => layout !== null, // predicate
);
// layout is the non-null currentLayout value

With Getters

Works with computed getters too:

const userBloc = await waitUntil(UserBloc, (bloc) => bloc.isReady);
const user = await waitUntil(
  UserBloc,
  (bloc) => bloc.currentUser,
  (user) => user !== null,
);

Options

interface WaitUntilOptions {
  instanceId?: string; // Target a specific instance (default: shared)
  timeout?: number; // Timeout in milliseconds
  signal?: AbortSignal; // Abort signal for cancellation
}

Timeout

try {
  const bloc = await waitUntil(UserBloc, (bloc) => bloc.state.isReady, {
    timeout: 5000,
  });
} catch (error) {
  if (error instanceof WaitUntilTimeoutError) {
    console.log('Timed out waiting for user');
  }
}

Abort Signal

const controller = new AbortController();

const promise = waitUntil(UserBloc, (bloc) => bloc.state.isReady, {
  signal: controller.signal,
});

// Cancel later
controller.abort();

Specific Instance

const bloc = await waitUntil(UserBloc, (bloc) => bloc.state.isReady, {
  instanceId: 'user-123',
});

Error Types

Error	When
WaitUntilTimeoutError	Timeout exceeded
WaitUntilAbortedError	AbortSignal triggered
WaitUntilDisposedError	Bloc disposed while waiting