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LESS - Import Options Once Keyword
Description
The @import (once) keyword ensures that the file is imported only once and any following import statements will be neglected for that file. This is the default behavior of the @import statements. This was released in version 1.4.0.
Example
The following example demonstrates the use of once keyword in the LESS file −
<html> <head> <link rel = "stylesheet" href = "style.css" type = "text/css" /> <title>Import Options Once</title> </head> <body> <h1>Welcome to Tutorialspoint</h1> <p class = "para_1">LESS is a CSS pre-processor that enables customizable, manageable and reusable style sheet for web site.</p> <p class = "para_2">LESS is a CSS pre-processor that enables customizable, manageable and reusable style sheet for web site.</p> </body> </html>
Now, create the style.less file.
style.less
@import (once) "http://www.tutorialspoint.com/less/once.less"; @import (once) "http://www.tutorialspoint.com/less/once.less"; // this statement will be ignored .para_1 { color: red; .style; } .para_2 { color: blue; }
The following code will import the once.less file into style.less from the https://www.tutorialspoint.com/less/once.less path −
once.less
.style { font-family: "Comic Sans MS"; font-size: 20px; }
You can compile the style.less to style.css by using the following command −
lessc style.less style.css
Execute the above command; it will create the style.css file automatically with the following code −
style.css
.style { font-family: "Comic Sans MS"; font-size: 20px; } .para_1 { color: red; font-family: "Comic Sans MS"; font-size: 20px; } .para_2 { color: blue; }
Output
Follow these steps to see how the above code works −
Save the above html code in the import_options_once.html file.
Open this HTML file in a browser, the following output will get displayed.