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JavaScript JavaScript Basics (Retired) Creating Reusable Code with Functions Passing an Argument to a Function

Megan Oliver
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Megan Oliver
Front End Web Development Techdegree Graduate 20,985 Points

Passing an Argument to a function

I can't seem to get this challenge to pass no matter what I do. Advice please?

script.js
function returnValue(favoriteToy) {
  return favoriteToy;
}

returnValue('yoyo');
var echo = returnValue;
index.html
<!DOCTYPE HTML>
<html>
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
  <title>JavaScript Basics</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>
Megan Oliver
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.a{fill-rule:evenodd;}techdegree seal-36
Megan Oliver
Front End Web Development Techdegree Graduate 20,985 Points

Sorry, here's the challenge:

After your newly created returnValue function, create a new variable named echo. Set the value of echo to be the results from calling the returnValue function. When you call the returnValue function, make sure to pass in any string you'd like for the parameter.

2 Answers

Your function declaration is correct. In the first line below you are simply calling the function without assigning the return value to anything. To assign the return value to a variable, you need to declare the variable and use the assignment operator followed by the call of the function, like so:

var variableName=functionName(functionArgument);

And in the challenge:

function returnValue(arg) {
 return arg; 
}

var echo=returnValue("string");
Trevor Johnson
Trevor Johnson
14,427 Points

Hi Megan, to start I would delete that return value that you have before var echo. Second, echo needs to be set equal to the function that you just created. To set the variable equal to a function think about how you would call a function normally apart from any variables, and how you pass in the argument that you want it to take. In this case you need to pass in an argument in the form of a string. The result is going to be a variable that stores the whole operation of the function after the argument has been passed in, and in this case it is simply the returned string passed into the function.