You can set the default values for variables by adding !default flag to the end of the variable value. It will not re-assign the value, if it is already assigned to the variable.
The following example demonstrates the use of variable defaults in the SCSS file −
<html> <head> <title>Variable Defaults</title> <link rel = "stylesheet" type = "text/css" href = "style.css" /> <link rel = "stylesheet" href = "https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css"> <script src = "https://ajax.googleapis.com/ajax/libs/jquery/2.1.3/jquery.min.js"></script> <script src = "https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script> </head> <body> <div class = "container"> <h2>Example using Variable Defaults</h2> <p>Sass is an extension of CSS that adds power and elegance to the basic language..</p> </div> </body> </html>
Next, create file style.scss.
$myval1: null; $myval1: "Sass Developed by Natalie Weizenbaum and Chris Eppstein" !default; p:after { content: $myval1; }
You can tell SASS to watch the file and update the CSS whenever SASS file changes, by using the following command −
sass --watch C:\ruby\lib\sass\style.scss:style.css
Next, execute the above command; it will create the style.css file automatically with the following code −
p:after { content: "Sass Developed by Natalie Weizenbaum and Chris Eppstein"; }
Let us carry out the following steps to see how the above given code works −
Save the above given html code in var_defaults.html file.
Open this HTML file in a browser, an output is displayed as shown below.