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LESS - Type Checking Functions
Description
You can use type checking built-in functions to determine the value types for matching mixins. To do this, you can use the is functions. Following is the list of available functions −
- iscolor
- isnumber
- isstring
- iskeyword
- isurl
The functions listed above are into basic type checking. You can check whether a value is in a specific unit or not by using the following functions −
- ispixel
- ispercentage
- isem
- isunit
Example
The following example demonstrates the use of type checking functions in the LESS file −
<!doctype html> <head> <title>Type Checking Functions</title> <link rel = "stylesheet" href = "style.css" type = "text/css" /> </head> <body> <h2>Example of Type Checking Functions</h2> <p class = "myclass">Hello World!!!Welcome to Tutorialspoint...</p> </body> </html>
Next, create the style.less file.
style.less
.mixin (@a; @b: red) when (iscolor(@b)){ color:blue; } .mixin (@a) { font-size: @a; } .myclass { .mixin(20px) }
You can compile the style.less to style.css by using the following command −
lessc style.less style.css
Now execute the above command; it will create the style.css file automatically with the following code −
style.css
.myclass { color: blue; font-size: 20px; }
Output
Follow these steps to see how the above code works −
Save the above html code in the type_checking_functions.html file.
Open this HTML file in a browser, the following output will get displayed.