Generated by SassMeister.com.

SassMeister-input.scss

// ----
// Sass (v3.3.4)
// Compass (v1.0.0.alpha.18)
// Bourbon (v)
// ----

@import "bourbon/bourbon";

$columns: one two three;
$length: length($columns);

@while $length > 0 {
  .block-#{nth($columns, $length)} {
    width:em(10*$length);
  }
  $length: $length - 1;
  }

SassMeister-output.css

.block-three {
  width: 1.875em;
}

.block-two {
  width: 1.25em;
}

.block-one {
  width: 0.625em;
}