Superscript Text in JavaScript: Ditching string.sup for Modern Practices

What is string.sup?

In JavaScript, string.sup (more accurately String.prototype.sup()) is a deprecated method that was intended to format a string as superscript text, similar to the HTML  tag. It would return a new string wrapped in  tags.

Why is it deprecated?

string.sup is considered deprecated because it mixes JavaScript (a programming language) with HTML (a markup language). This can lead to messy and less maintainable code. Additionally, it doesn't guarantee the correct rendering of the superscript text in all browsers.

How to achieve superscript formatting

For modern JavaScript practices, here are the recommended ways to format text as superscript:

Using HTML elements
This is the preferred approach as it separates concerns and leverages the strengths of both languages. You can create an element using DOM manipulation and set its content to the desired text:
```
const supElement = document.createElement('sup');
supElement.textContent = 'This is superscript text';
document.body.appendChild(supElement);
```

Using CSS styles

If you need more control over the styling of the superscript text, you can apply CSS styles to an element with the class name superscript:

const textElement = document.createElement('span');
textElement.textContent = 'This is superscript text';
textElement.classList.add('superscript');
document.body.appendChild(textElement);

// In your CSS
.superscript {
    vertical-align: super;
    font-size: smaller; /* Adjust font size as needed */
}

<!DOCTYPE html>
<html>
<head>
<title>Superscript Example</title>
</head>
<body>
  <p>The speed of light is <sup>299,792,458</sup> meters per second.</p>

  <script>
    // Alternative (not recommended in this case as the element already exists)
    // const supElement = document.querySelector('sup');
    // supElement.textContent = '299,792,458';
  </script>
</body>
</html>

The browser interprets the  tag and renders the text within it as superscript.
This code creates a paragraph element () with the text "The speed of light is" and an  element containing the superscript value (299,792,458).

<!DOCTYPE html>
<html>
<head>
<title>Superscript Example</title>
<style>
  .superscript {
    vertical-align: super;
    font-size: 80%; /* Adjust font size as needed */
  }
</style>
</head>
<body>
  <p>The speed of light is <span class="superscript">299,792,458</span> meters per second.</p>
</body>
</html>

The CSS style defines the formatting for the .superscript class, setting vertical-align: super to raise the text and font-size (adjusted as needed) to make it smaller.
Instead of using the  tag, it uses a  element with the class name "superscript".
This code creates a paragraph element () similar to the previous example.