Generated by SassMeister.com.

SassMeister-input.scss

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

@mixin some-color-name($color) {
  @if type-of($color) == 'map' {
     background-image: linear-gradient(map-get($color, key1), map-get($color, key2));
   }
}

$derp: (key1: #ddd, key2: #ff0);

.div {
  @include some-color-name($derp);
}

SassMeister-output.css

.div {
  background-image: linear-gradient(#dddddd, yellow);
}