Front-end Tutorials

Front-end Tutorials

HTMLCSSSassJavaScriptReactJS
CMS Tutorials

CMS Tutorials

WordPress
Tutorials expand

Sass Introspection

Sass feature-exists() Function

Posted in Sass Tutorial
Updated on Sep 30, 2024
By Mari Selvan
πŸ‘οΈ 11 - Views
⏳ 4 mins
πŸ’¬ 1 Comment
Sass feature-exists() Function

Photo Credit to CodeToFun

πŸ™‹ Introduction

The feature-exists() function in Sass is used to check if a particular feature is available in the current Sass implementation.

This function is particularly useful when writing cross-version compatible code or when you want to ensure that certain features are available before using them in your stylesheets.

πŸ’‘ Syntax

The syntax of the feature-exists() function is simple and straightforward. It takes one argument, which is the name of the feature you want to check for.

Syntax
Copied
Copy To Clipboard
feature-exists($feature-name)

πŸ”’ Parameters

  • $feature-name: The name of the feature you wish to check. This is a string and should be the exact name of the feature as recognized by Sass.

↩️ Return Value

The function returns a Boolean value:

  • true: if the feature is available.
  • false: if the feature is not available.

🌟 Common Features to Check

Some commonly checked features include:

  • "global-variable-shadowing": Checks if global variable shadowing is supported.
  • "at-error": Checks if the @error directive is supported.
  • "units-level-3": Checks if level 3 units are supported.
  • "custom-properties": Checks if CSS custom properties (variables) are supported.

πŸ“ Example Usage

Let’s explore some practical examples of how to use feature-exists() in your Sass projects.

πŸ“œ Example 1: Basic Feature Check

example.scss
Copied
Copy To Clipboard
@if feature-exists("global-variable-shadowing") {
  $color: blue;
  @debug "Global variable shadowing is supported.";
} else {
  @debug "Global variable shadowing is not supported.";
}

In this example, the code checks if the "global-variable-shadowing" feature is supported in the current Sass environment and outputs a debug message accordingly.

πŸ“œ Example 2: Conditionally Using Features

example.scss
Copied
Copy To Clipboard
$use-new-feature: false;

@if feature-exists("at-error") {
  $use-new-feature: true;
}

@if $use-new-feature {
  @error "This is a custom error message.";
} else {
  @warn "The @error directive is not supported.";
}

This example demonstrates how you can conditionally use a feature based on its availability. If the @error directive is supported, it will be used; otherwise, a warning is issued.

πŸ“œ Example 3: Checking for Units-Level-3 Support

example.scss
Copied
Copy To Clipboard
@if feature-exists("units-level-3") {
  $spacing: 1rem;
} else {
  $spacing: 16px;
}

.container {
  margin: $spacing;
}

Here, the code checks if level 3 units are supported. If they are, it uses rem units; otherwise, it falls back to px.

πŸŽ‰ Conclusion

The feature-exists() function in Sass is a powerful tool for ensuring compatibility and making your stylesheets more robust. By using this function, you can write conditional code that adapts to the capabilities of the current Sass environment, avoiding potential errors or unsupported features.

This function is particularly useful in larger projects or libraries where you want to maintain compatibility across different Sass versions or implementations. By leveraging feature-exists(), you can enhance the reliability and flexibility of your Sass code, ensuring it works seamlessly across various environments.

πŸ‘¨β€πŸ’» Join our Community:

To get interesting news and instant updates on Front-End, Back-End, CMS and other Frameworks. Please Join the Telegram Channel:

Author

author
πŸ‘‹ Hey, I'm Mari Selvan

For over eight years, I worked as a full-stack web developer. Now, I have chosen my profession as a full-time blogger at codetofun.com.

Buy me a coffee to make codetofun.com free for everyone.

Buy me a Coffee

Share Your Findings to All

Subscribe
Notify of
guest
1 Comment
Oldest
Newest Most Voted
Inline Feedbacks
View all comments
We make use of cookies to improve our user experience. By using this website, you agree with our Cookies Policy
AgreeCookie Policy