freeCodeCamp/curriculum/challenges/english/02-javascript-algorithms-an.../basic-javascript/passing-values-to-functions...

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---
id: 56533eb9ac21ba0edf2244bd
title: Passing Values to Functions with Arguments
challengeType: 1
---
## Description
<section id='description'>
<dfn>Parameters</dfn> are variables that act as placeholders for the values that are to be input to a function when it is called. When a function is defined, it is typically defined along with one or more parameters. The actual values that are input (or <dfn>"passed"</dfn>) into a function when it is called are known as <dfn>arguments</dfn>.
Here is a function with two parameters, <code>param1</code> and <code>param2</code>:
<blockquote>function testFun(param1, param2) {<br>&nbsp;&nbsp;console.log(param1, param2);<br>}</blockquote>
Then we can call <code>testFun</code>:
<code>testFun("Hello", "World");</code>
We have passed two arguments, <code>"Hello"</code> and <code>"World"</code>. Inside the function, <code>param1</code> will equal "Hello" and <code>param2</code> will equal "World". Note that you could call <code>testFun</code> again with different arguments and the parameters would take on the value of the new arguments.
</section>
## Instructions
<section id='instructions'>
<ol><li>Create a function called <code>functionWithArgs</code> that accepts two arguments and outputs their sum to the dev console.</li><li>Call the function with two numbers as arguments.</li></ol>
</section>
## Tests
<section id='tests'>
```yml
tests:
- text: <code>functionWithArgs</code> should be a function
testString: 'assert(typeof functionWithArgs === ''function'', ''<code>functionWithArgs</code> should be a function'');'
- text: '<code>functionWithArgs(1,2)</code> should output <code>3</code>'
testString: 'if(typeof functionWithArgs === "function") { capture(); functionWithArgs(1,2); uncapture(); } assert(logOutput == 3, ''<code>functionWithArgs(1,2)</code> should output <code>3</code>'');'
- text: '<code>functionWithArgs(7,9)</code> should output <code>16</code>'
testString: 'if(typeof functionWithArgs === "function") { capture(); functionWithArgs(7,9); uncapture(); } assert(logOutput == 16, ''<code>functionWithArgs(7,9)</code> should output <code>16</code>'');'
- text: Call <code>functionWithArgs</code> with two numbers after you define it.
testString: 'assert(/^\s*functionWithArgs\s*\(\s*\d+\s*,\s*\d+\s*\)\s*;/m.test(code), ''Call <code>functionWithArgs</code> with two numbers after you define it.'');'
```
</section>
## Challenge Seed
<section id='challengeSeed'>
<div id='js-seed'>
```js
// Example
function ourFunctionWithArgs(a, b) {
console.log(a - b);
}
ourFunctionWithArgs(10, 5); // Outputs 5
// Only change code below this line.
```
</div>
### Before Test
<div id='js-setup'>
```js
var logOutput = "";
var originalConsole = console
function capture() {
var nativeLog = console.log;
console.log = function (message) {
if(message) logOutput = JSON.stringify(message).trim();
if(nativeLog.apply) {
nativeLog.apply(originalConsole, arguments);
} else {
var nativeMsg = Array.prototype.slice.apply(arguments).join(' ');
nativeLog(nativeMsg);
}
};
}
function uncapture() {
console.log = originalConsole.log;
}
capture();
```
</div>
### After Test
<div id='js-teardown'>
```js
console.info('after the test');
```
</div>
</section>
## Solution
<section id='solution'>
```js
function functionWithArgs(a, b) {
console.log(a + b);
}
functionWithArgs(10, 5);
```
</section>