Generated by SassMeister.com.

SassMeister-input-HTML.html

<div class="EditorialPromo media">
  <header class="EditorialPromo media-headline">
    Editorial Promo
  </header>
</div>

SassMeister-input.scss

// ----
// libsass (v3.3.2)
// ----

@mixin block($block) {
  @at-root .#{$block} {
    @content;
  }
}

%module {
 margin: 5px;
 padding: 2px;
}

// Block alias
@mixin module($args...) {
  @include block($args...) {
    @extend %module;
    @content;
  };
}

@mixin element($element) {
  @at-root #{&}-#{$element} {
    @content;
  }
}

%normal-headline {
  font-size: 32px;
}

@mixin headline($type) {
  @include element('#{$type}-headline') {
    @extend #{$type}-headline;
    @content;
  }
}

@mixin modifier($modifier) {
  @extend &;
  @at-root #{&}--#{$modifier} {
    @content;
  }
}

// Definition
/*
@include module('EditorialPromo') {
  test: $this;
  
  @include headline() {
    type: $editorialPromo-headline;
  }
  
}
*/

.EditorialPromo {
  //@extend %module;
  test: this;
  
  &-headline {
    //@extend %normal-headline;
    type: headline;
  }
  
}

SassMeister-output.css

/*
@include module('EditorialPromo') {
  test: $this;
  
  @include headline() {
    type: $editorialPromo-headline;
  }
  
}
*/
.EditorialPromo {
  test: this;
}

.EditorialPromo-headline {
  type: headline;
}

SassMeister-rendered.html

<div class="EditorialPromo media">
  <header class="EditorialPromo media-headline">
    Editorial Promo
  </header>
</div>