arrayToString.scss

@function arrayToString($list, $separator: " ") {
  $str: null;
  @each $item in $list {
    $i: index($list, $item);
    @if $i == 1 {
      $str: $str #{$item};
    }
    @else {
      $str: $str#{$separator} #{$item};
    }
  }
  @return $str;
}

Sass function to join e.g. (#222 #333 #444) to "#222 #333 #444".