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SassMeister-input-HTML.html

<div class="class">asd</div>

SassMeister-input.scss

// ----
// Sass (v3.4.4)
// Compass (v1.0.1)
// ----

//since 3.4 index() now returns null rather than false if the value isn’t found in the list.
$list: ();
.test {
  @if index($list, test) == null {
    $list: append($list,test);
  }
  content: $list; //I expected this to print 'test'...
}

SassMeister-output.css

() isn't a valid CSS value.

SassMeister-rendered.html

<div class="class">asd</div>