<===> input.scss
div {
  $x: 3;
  @each $x in singleton {
    color: $x;
  }
  divider: $x;
  @each $x in foo, bar, hux {
    span {
      msg: $x;
    }
  }
}
<===> output.css
div {
  color: singleton;
  divider: 3;
}
div span {
  msg: foo;
}
div span {
  msg: bar;
}
div span {
  msg: hux;
}