Generated by SassMeister.com.

SassMeister-input.scss

// ----
// Sass (v3.4.9)
// Compass (v1.0.1)
// ----

@mixin font-headline($type, $color: "") {

    @if $type == h1 {
        $font-size-headline: 28;
    } @else if $type == h2 {
        $font-size-headline: 24;
    } @else if $type == h3 {
        $font-size-headline: 20;
        /* ... */
    } @else {
        @error 'Missing headline type';
    }

    @if $color == orange {
        color: #f90;
    } @else if $color == black or $color == default {
        color: #111;
    }

    font: 700 #{$font-size-headline}/1.25 Arial, sans-serif;

}

.foo {
  @include font-headline(h1);
}

.bar {
  @include font-headline(h2, orange);
}

SassMeister-output.css

Undefined variable: "$font-size-headline".