@import and @require

Stylus supports both literal @import for CSS, as well as dynamic importing or requiring of other Stylus sheets.

Literal CSS

Any filename with the extension .css will become a literal. For example:

 @import "reset.css"

Render the literal CSS @import shown below:

 @import "reset.css"

Stylus Import

Disclaimer: In all places the @import is used with Stylus sheets, the @require could be used

When using @import without the .css extension, it’s assumed to be a Stylus sheet (e.g., @import "mixins/border-radius").

@import works by iterating an array of directories, and checking if this file lives in any of them (similar to node’s require.paths). This array defaults to a single path, which is derived from the filename option’s dirname. So, if your filename is /tmp/testing/stylus/main.styl, then import will look in /tmp/testing/stylus/.

@import also supports index styles. This means when you @import blueprint, it will resolve either blueprint.styl or blueprint/index.styl. This is really useful for libraries that want to expose all their features, while still allowing feature subsets to be imported.

For example, a common lib structure might be:

./tablet
  |-- index.styl
  |-- vendor.styl
  |-- buttons.styl
  |-- images.styl

In the example below, we set the paths options to provide additional paths to Stylus. Within ./test.styl, we could then @import "mixins/border-radius", or @import "border-radius" (since ./mixins is exposed to Stylus).

  /**
   * Module dependencies.
   */

  var stylus = require('../')
    , str = require('fs').readFileSync(__dirname + '/test.styl', 'utf8');

  var paths = [
      __dirname
    , __dirname + '/mixins'
  ];

  stylus(str)
    .set('filename', __dirname + '/test.styl')
    .set('paths', paths)
    .render(function(err, css){
      if (err) throw err;
      console.log(css);
    });

Require

Along with @import, Stylus also has @require. It works almost in the same way, with the exception of importing any given file only once.

Block-level import

Stylus supports block-level import. It means that you can use @import not only at root level, but also nested inside other selectors or at-rules.

If you have a bar.styl with this code:

.bar
  width: 10px;

Then you can import it inside a foo.styl like this:

.foo
  @import 'bar.styl'

@media screen and (min-width: 640px)
  @import 'bar.styl'

And you’ll get this compiled CSS as a result:

.foo .bar {
  width: 10px;
}
@media screen and (min-width: 640px) {
  .bar {
    width: 10px;
  }
}

File globbing

Stylus supports globbing. With it you could import many files using a file mask:

@import 'product/*'

This would import all the stylus sheets from the product directory in such structure:

./product
  |-- body.styl
  |-- foot.styl
  |-- head.styl

Note that this works with @require too, so if you would have also a ./product/index.styl with this content:

@require 'head'
@require 'body'
@require 'foot'

then @require 'product/*' would include each individual sheet only once.

Resolving relative urls inside imports

By default Stylus doesn’t resolve the urls in imported .styl files, so if you’d happen to have a foo.styl with @import "bar/bar.styl" which would have url("baz.png"), it would be url("baz.png") too in a resulting CSS.

But you can alter this behavior by using --resolve-url (or just -r) CLI option to get url("bar/baz.png") in your resulting CSS.

JavaScript Import API

When using the .import(path) method, these imports are deferred until evaluation:

   var stylus = require('../')
     , str = require('fs').readFileSync(__dirname + '/test.styl', 'utf8');

   stylus(str)
     .set('filename', __dirname + '/test.styl')
     .import('mixins/vendor')
     .render(function(err, css){
     if (err) throw err;
     console.log(css);
   });

The following statement…

 @import 'mixins/vendor'

…is equivalent to…

 .import('mixins/vendor')