121 lines
2.9 KiB
Markdown
121 lines
2.9 KiB
Markdown
---
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id: 56533eb9ac21ba0edf2244bd
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title: Passing Values to Functions with Arguments
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challengeType: 1
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videoUrl: 'https://scrimba.com/c/cy8rahW'
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forumTopicId: 18254
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dashedName: passing-values-to-functions-with-arguments
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---
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# --description--
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<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>.
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Here is a function with two parameters, `param1` and `param2`:
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```js
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function testFun(param1, param2) {
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console.log(param1, param2);
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}
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```
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Then we can call `testFun` like this: `testFun("Hello", "World");`. We have passed two string arguments, `Hello` and `World`. Inside the function, `param1` will equal the string `Hello` and `param2` will equal the string `World`. Note that you could call `testFun` again with different arguments and the parameters would take on the value of the new arguments.
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# --instructions--
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<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>
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# --hints--
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`functionWithArgs` should be a function.
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```js
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assert(typeof functionWithArgs === 'function');
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```
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`functionWithArgs(1,2)` should output `3`.
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```js
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if (typeof functionWithArgs === 'function') {
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capture();
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functionWithArgs(1, 2);
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uncapture();
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}
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assert(logOutput == 3);
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```
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`functionWithArgs(7,9)` should output `16`.
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```js
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if (typeof functionWithArgs === 'function') {
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capture();
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functionWithArgs(7, 9);
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uncapture();
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}
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assert(logOutput == 16);
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```
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You should call `functionWithArgs` with two numbers after you define it.
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```js
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assert(
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/functionWithArgs\([-+]?\d*\.?\d*,[-+]?\d*\.?\d*\)/.test(
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code.replace(/\s/g, '')
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)
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);
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```
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# --seed--
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## --before-user-code--
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```js
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var logOutput = "";
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var originalConsole = console
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function capture() {
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var nativeLog = console.log;
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console.log = function (message) {
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if(message) logOutput = JSON.stringify(message).trim();
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if(nativeLog.apply) {
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nativeLog.apply(originalConsole, arguments);
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} else {
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var nativeMsg = Array.prototype.slice.apply(arguments).join(' ');
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nativeLog(nativeMsg);
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}
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};
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}
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function uncapture() {
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console.log = originalConsole.log;
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}
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capture();
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```
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## --after-user-code--
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```js
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uncapture();
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if (typeof functionWithArgs !== "function") {
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(function() { return "functionWithArgs is not defined"; })();
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} else {
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(function() { return logOutput || "console.log never called"; })();
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}
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```
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## --seed-contents--
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```js
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```
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# --solutions--
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```js
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function functionWithArgs(a, b) {
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console.log(a + b);
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}
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functionWithArgs(10, 5);
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```
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