Less.js is a simple CSS pre-processor that facilitates the creation of manageable, customizable, and reusable style sheets for websites. It is a dynamic style sheet language that improves CSS’s functionality. Cross-browser interoperability is supported by LESS. A scripting language known as CSS pre-processor is used to enhance CSS and compile it into standard CSS syntax for use by web browsers. Additionally, it is a language extension for CSS that supports backward compatibility and offers functionality like variables, functions, mixins, and operations that let us create dynamic CSS.
Less.js Logical boolean() Function receives a condition and, depending on it, outputs True or False. Generally, you can use this method to save a condition’s result in a variable so that you can utilize it later, as needed, in an “if” function.
Syntax:
boolean(condition);
Parameters:
- condition: This is the parameter that is compulsory for the boolean function, this condition is evaluated and the result is returned.
Example 1: The code below demonstrates how we can use the boolean Logical function in Less.js and we can pair it with another LESS function to produce an output.
index.html
<!DOCTYPE html> <html> <head> <link rel="stylesheet" type="text/css" href="style.css"/> </head> <body> <h1>neveropen</h1> <h3>Less.js Logical boolean() Function</h3> </body> </html> |
styles.less
@body-bg-color: #eeeeee; @text-color: rgb(70, 172, 121); @button-bg-color: boolean(color(@body-bg-color) = #a7a7a7); body { background: @body-bg-color; } h3{ color: if(@button-bg-color, grey, green); } |
Now, to compile the above LESS code to CSS code, run the following command:
lessc styles.less styles.css
The compiled CSS file comes to be:
style.css
body { background: #eeeeee; } h3 { color: green; } |
Output:
Example 2: The code below demonstrates how we can use multiple boolean Logical functions in Less.js and we can pair them with various LESS functions to produce an output.
index.html
<!DOCTYPE html> <html> <head> <link rel="stylesheet" type="text/css" href="style.css"/> </head> <body> <h1>neveropen</h1> <h3>Less.js Logical boolean() Function</h3> <div class="container"> </div> </body> </html> |
styles.less
/* styles.less */@body-bg-color: #eeeeee; @text-color: rgb(71, 167, 119); @container-bg: rgb(220, 43, 55); @cond1: boolean(luma(@body-bg-color) > 50%); @cond2: boolean(luma(@container-bg) > 50%); body { background: @body-bg-color; } h3{ color: if(@cond2, grey, green); } .container{ width: 15rem; height: 9rem; background-color: if(@cond1, @container-bg, @button-bg-color); } |
Now, to compile the above LESS code to CSS code, run the following command:
lessc styles.less styles.css
The compiled CSS file comes to be:
style.css
body { background: #eeeeee; } h3 { color: green; } .container { width: 15rem; height: 9rem; background-color: #dc2b37; } |
Output:
Reference: https://lesscss.org/functions/#logical-functions-boolean
