Generated by SassMeister.com.

SassMeister-input.scss

// ----
// Sass (v3.3.0.rc.1)
// Compass (v0.13.alpha.10)
// ----

//elements get appended with "__" and the $name
@mixin e($name) {
  @at-root   #{&}__#{$name} {
    @content;
  }
}

//modifiers get appended with "--" and the $name
@mixin m($name) {
  @at-root   #{&}--#{$name} {
    @content;
  }
}

.link {
    background: red;
    @include m(test) {
        background: blue;
    }
    @include e(tester) {
        background: orange;
    }
}

SassMeister-output.css

.link {
  background: red;
}
.link--test {
  background: blue;
}
.link__tester {
  background: orange;
}