Generated by SassMeister.com.

SassMeister-input.scss

// ----
// libsass (v3.2.5)
// ----

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

.absolutely-centered-with-class{
  position:absolute;
  top:0;
  bottom:0;
  left:0;
  right:0;
  margin:auto;
}
%absolutely-centered-without-class{
  position:absolute;
  top:0;
  bottom:0;
  left:0;
  right:0;
  margin:auto;
}

#some-div{
  @extend .absolutely-centered-with-class;
}
#some-other-div{
  @extend %absolutely-centered-without-class;
}
#some-completely-other-div{
  @extend %absolutely-centered-without-class;
}

SassMeister-output.css

.absolutely-centered-with-class, #some-div {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  margin: auto;
}

#some-other-div, #some-completely-other-div {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  margin: auto;
}