Here is an example of how you can integrate JavaScript in `fastn` functions. Suppose we have a JavaScript function `show_alert` defined in `functions.js` as follows:

`functions.js`

function show_alert(a) {
alert(a);
}

Lang:

Now, let's say we want to call this function when a user clicks a text in an `fastn` component. Here's how we can achieve this in `index.ftd`:

`index.ftd`

-- ftd.text: Click here to print name in alert!
$on-click$: $call-js-fn(a = FifthTry Alert)

-- void call-js-fn(a):
string a:
js: functions.ftd

show_alert(a)

Lang:

ftd

In the above example, when the user clicks the text component, the `call-js-fn` function is called, passing the `FifthTry` value to the argument `a`. This function, then, references `functions.js` by using the `js` attribute and calls the `show_alert` function.

Output

Click here to print name in alert!

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