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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              const root = document.getElementById('root')
const bus = new Bulb.Bus()

// A signal that searches for books by ISBN and emits the result as a new state.
const searchSignal = bus
  // Don't bother searching for empty queries.
  .filter(a => a !== '')

  // Search for the book using the API.

  // Create a new state.
  .map(result => ({ result, loading: false }))

// A signal that emits a loading state while the request is processing.
const loadingSignal = bus.always({ result: null, loading: true })

// Start with the default state and re-render the view when the other signals emit values.
Bulb.Signal.of({ result: null, loading: false })
  .merge(searchSignal, loadingSignal)
    state => ReactDOM.render(<RootView bus={bus} loading={state.loading} result={state.result} />, root)

// Returns a signal that emits the result of the search request to the API.
function findBook (isbn) {
  const url = `${isbn}`
  return Bulb.Signal
    .fromPromise(fetch(url).then(response => response.json()))
      data => data.totalItems > 0 ? data.items[0].volumeInfo.title : null

function RootView ({ bus, loading, result }) {
  const [query, setQuery] = React.useState('')

  return (
    <div className='jumbotron jumbotron-fluid'>
      <div className='container'>
        <h1>Book Search 📚</h1>
        <p className='lead'>This example demonstrates using a signal to handle an AJAX request.</p>
        <p>Enter an ISBN to find on Google Books (e.g. 0747532699).</p>
        <div class='input-group mb-3'>
          <input className='form-control' onChange={event => setQuery(} placeholder='ISBN' type='text' />
          <div className='input-group-append'>
            <Button disabled={loading} onClick={() =>}>
              {loading ? <Spinner /> : null}
        {result ? <pre>{result}</pre> : null}

function Button ({ children, disabled, onClick }) {
  return (
    <button className='btn btn-primary' disabled={disabled} onClick={onClick}>{children}</button>

function Spinner () {
  return (
      <span className='spinner-grow spinner-grow-sm' role='status' aria-hidden='true'></span>
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