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CSS

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JavaScript

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Babel includes JSX processing.

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HTML 

              
                <html>
  <body>
    <h1>UI callback function</h1>
    <button maxValue="100">Primes up to 100</button><p/>
    <button maxValue="10000">Primes up to 10,000</button><p/>
    <button maxValue="10000000">Primes up to 10,000,000</button><p/>
    <button maxValue="10000000000">Primes up to 10,000,000,000</button>
    <p>
      Resulting primes: <div id="result">Waiting for click...</div></p>
  </body>
</html>
!

CSS
!

JS 

              
                console.log("About to add UI callbacks");
const result = document.getElementById("result");
const btns = document.getElementsByTagName("button");
for (let k = 0; k < btns.length; k++) {
  btns[k].addEventListener("click", primeNumbersTo);
}


function primeNumbersTo(event)
{
    const max = event.target.getAttribute("maxValue");
    var store  = [], i, j, primes = [];
    for (let i = 2; i <= max; ++i) 
    {
        if (!store [i]) 
          {
            primes.push(i);
            for (let j = i << 1; j <= max; j += i) 
            {
                store[j] = true;
            }
        }
    }
    console.log("Primes from max %s: %s", max, primes);
    result.innerHTML = primes
    return primes;
}

console.log("Finished adding UI callbacks")
console.log("I'm a really urgent log message");
!
999px

Console