<===> input.scss
$x: -42;
$y: -84;
div {
  x: $x;
  y: $y;
  for {
    x: $x;
    y: $y;
    @for $x from 1 through 5 {
      $y: $y + 5;
      x: $x;
      y: $y;
      $x: 999;
      $y: -9 !global;
      $x: -9 !global;
    }
    x: $x;
    y: $y;
  }
  x: $x;
  y: $y;
}
<===> output.css
div {
  x: -42;
  y: -84;
  x: -9;
  y: -9;
}
div for {
  x: -42;
  y: -84;
  x: 1;
  y: -79;
  x: 2;
  y: -74;
  x: 3;
  y: -69;
  x: 4;
  y: -64;
  x: 5;
  y: -59;
  x: -9;
  y: -9;
}