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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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.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

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