@emception/react

React 19 components for emception.

Install

npm install @emception/react @emception/webcomponent @emception/browser

<EmceptionRun>

Declarative wrapper around the <emception-run> custom element.

'use client';

import { useCallback } from 'react';
import { EmceptionRun, useEmception } from '@emception/react';
import { createEmception } from '@emception/browser';

// Register the custom element on the client (NOT in the server bundle).
import '@emception/webcomponent';

export function Demo() {
  const create = useCallback((signal: AbortSignal) => {
    return createEmception({ tty: 'none', signal });
  }, []);
  const { api, status, error } = useEmception({ create });

  if (status === 'error') return <pre>{String(error)}</pre>;

  return (
    <EmceptionRun
      api={api}
      preset="cpp"
      autorun
      source="int main(){ return 0; }"
      onStdout={(p) => console.log(p.chunk)}
      onExit={(p) => console.log('exit', p.code)}
    />
  );
}

Props

• All ViewConfigInput fields as camelCase props (e.g. manifestUrl, seedUrl, buildUrl, autorun, canvas, showHidden, …).
• Typed event-handler props derived from EmceptionEventMap: onReady, onStdout, onStderr, onExit, onTestReport, onTestCase, …
• api?: EmceptionAPI | null — attaches a pre-built API to the host element via its setter.
• className, style, children — forwarded.

Non-primitive props (e.g. a fully-shaped workspace object) are not projected as attributes; pass them through useEmception's create factory and attach the resulting api instead.

Imperative ref

const ref = useRef<EmceptionRunHandle>(null);
// ref.current.element  → HTMLElement | null
// ref.current.api      → EmceptionAPI | null

useEmception(opts)

const { api, status, error } = useEmception({
  create: (signal) => createEmception({ signal }),
  skip: false,
});

• create(signal) — your factory. Wrap in useCallback to avoid rebuilding the API on every render.
• skip — short-circuit (e.g. for SSR).
• Returns { api, status: 'idle' | 'loading' | 'ready' | 'error', error }.
• Aborts in-flight builds on unmount and disposes the api.

SSR

@emception/react itself does not import @emception/webcomponent — that package self-registers the custom element on import, which would fail on the server. Register the element from a client-only entry (e.g. inside a 'use client' component or useEffect).