/**
 * A mixin for generating a rule.
 */
@mixin test-mixin {

  /**
   * A function to help with something.
   *
   * @param {int} $a
   *   The $a.
   * @param {int} $b
   *   The $b
   *
   * @return {bool}
   *   true if $a is greater than $b, false otherwise.
   */
  @function greater($a, $b) {
    // Check if a is greater than b
    @return $a > $b;
  }

  .one-liner { color: red; /* Sets the color */ border: 1px; /* Add a border */ }

  // Do some logic based on the function call.
  @if (greater(2, 2)) {
    /* all good here. */
  }
  @else { /* Never gets called */
    /* If we get here, warn somebody */
    @warn "how'd I get here?";
  }

}