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JavaScript Callback Functions in JavaScript Introduction to Callback Functions Using a Function as a Callback

Kevin Lewis
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Kevin Lewis
Front End Web Development Techdegree Student 9,667 Points
Posted by Kevin Lewis
.a{fill-rule:evenodd;}techdegree
Kevin Lewis
Front End Web Development Techdegree Student 9,667 Points

Help Creating an Anonymous Callback Function

Keep getting either a syntax error or that the log didn’t go through the functionRunner. Help would be appreciated,

app.js 
function log() {
  console.log("Hello World!");
}

functionRunner(log);



functionRunner(function() {
  console.log("Hello World!");
})
index.html 
<!DOCTYPE html>
<html lang="en">
    <head>
        <title></title>
        <link rel='stylesheet' href='styles.css'>
    </head>
    <body>
        <section>
            <p>Open your browser's console to see the results</p>
        </section>
        <script src='runner.js'></script>
        <script src='app.js'></script>
    </body>
</html>
runner.js 
function functionRunner(callback) { 
  callback();
}

1 Answer

Dylan Glover
Dylan Glover
2,525 Points
Dylan Glover
Dylan Glover
2,525 Points

Pretty sure this is all you need in your app.js to callback the log as an anonymous function:

functionRunner(function () {
  console.log("Hello World!");
});

Hope that helps, Dylan