Generated by SassMeister.com.

SassMeister-input.scss

// ----
// Sass (v3.4.0.rc.1)
// Compass (v1.0.0.alpha.20)
// ----

@mixin context($old-context, $new-contexts...) {
  @each $context in $new-contexts {
    @at-root #{selector-replace(&, $old-context, $context)} {
        @content;
    }
  }
}

.tabs {
    .tab {
        background: red;
        &:hover {
            background: white;
        }
        .tab-link {
            color: white;
            @include context('.tab', '.tab:hover', '.tab.active') {
                color: red;
            }
        }
    }
}

SassMeister-output.css

.tabs .tab {
  background: red;
}
.tabs .tab:hover {
  background: white;
}
.tabs .tab .tab-link {
  color: white;
}
.tabs .tab:hover .tab-link {
  color: red;
}
.tabs .tab.active .tab-link {
  color: red;
}