Generated by SassMeister.com.

SassMeister-input.scss

// ----
// libsass (v2.0.0)
// ----

@mixin equivalent_fractions($numerator,$denominator){
    @for $i from -$numerator through -1{
        @if($numerator % abs($i) == 0 and $denominator % abs($i) == 0){
            out: #{$numerator / abs($i)}-#{$denominator / abs($i)};
        }
    }
}

.test{
    @include equivalent_fractions(8,12);
}

SassMeister-output.css

.test {
  out: 2-3;
  out: 4-6;
  out: 8-12; }