An JavaScript inline function is a function assigned to a variable that is created at runtime instead of at parsetime. Consider an inline function to be a special case of a JavaScript function.
var func = function() { //Code };
Inline functions could also be declared with the more compact, arrow function syntax.
JavaScript inline function
Simple example code.
<!DOCTYPE html>
<html>
<body>
<script>
var foo = function (){
alert('Inline function')
}
setTimeout(foo, 100);
</script>
</body>
</html>
Output:

More Example
<script>
var func = function() {
alert ('inline')
};
$('a').click(func);
// Alternative es6+ inline arrow function.
let func2 = () => alert('inline');
$('a').click(func2);
</script>
Inline JavaScript onclick function
You can use Self-Executing Anonymous Functions. this code will work:
<a href="#" onClick="(function(){
alert('Hey i am calling');
return false;
})();return false;">click here</a>
Or
You may inline any javascript inside the onclick as if you were assigning the method through javascript.Make code cleaner keeping your js inside a script block.
<a href="#" onclick="function hi(){alert('Hi!')};hi()">click</a>
Do comment if you have any doubts or suggestions on this JS function topic.
Note: The All JS Examples codes are tested on the Firefox browser and the Chrome browser.
OS: Windows 10
Code: HTML 5 Version

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