Compass - Custom sprite

sprite-example.scss

@import "compass/utilities/sprites/base";

$icons: sprite-map("images/icons/*.png", $layout: smart);

[class^="icon-"] {
  display: inline-block;
  background: $icons;
}

@each $i in sprite_names($icons) {
  .icon-#{$i} {
    background-position: sprite-position($icons, $i);
    @include sprite-dimensions($icons, $i);
  } 
}