embd/bower_components/gumby/sass/functions/_icons.scss

@function match($list, $icon) {
  @each $item in $list {
    $index: index($item, $icon);
      @if $index {
        $return: if($index == 1, 2, $index);
        @return nth($item, $return);
      }
    }
  @return false;
}

@mixin i($icon) {
  .#{$icon}.icon-left a:before,
  .#{$icon}.icon-right a:after,
  i.#{$icon}:before {
    content: "#{match($entypo-icons, $icon)}";
    height: inherit;
  }
}

@mixin icon($icon) {
  @if (type-of($icon) == list) {
    @each $i in $icon {
      @include i($i);
    }
  }
  @elseif ($icon == all) {
    @each $icon in $entypo-icons {
      @include i(nth($icon, 1));
    }
  }
  @else {
    @include i($icon);
  }
}