Preloading svg's the Sass way

SassMeister-input.scss

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

$preloaded-images: null;

$svg-path:'test/';

@function preload-image($image-url) {
  $preloaded-images : $preloaded-images  url($image-url) !global;
  @return $preloaded-images;
}


@mixin background-image-svg($img-name) {
  background-image: url($svg-path + $img-name + ".svg");
  // This function will add the image to the list of images to preload.
   $tmp: preload-image($svg-path + $img-name + ".svg");

}

.cool-class {
  @include background-image-svg('a');
  @include background-image-svg('b');
}
.cooler {
  @include background-image-svg('d');
  @include background-image-svg('f');
}
body:before {
  display: none;
  content: $preloaded-images;
}

SassMeister-output.css

.cool-class {
  background-image: url("test/a.svg");
  background-image: url("test/b.svg");
}

.cooler {
  background-image: url("test/d.svg");
  background-image: url("test/f.svg");
}

body:before {
  display: none;
  content: url("test/a.svg") url("test/b.svg") url("test/d.svg") url("test/f.svg");
}