add multiple box-shadows in compass pre-v.11

multi-shadow SCSS

// Example Usage

@include multi-shadow(rgba(0,0,0,.35) 0 2px 3px 0 inset, rgba(255,255,255,.5) 0 1px 2px);

// Actual Mixin. For Compass versions prior to v.11,
// when the box-shadow syntax changed to do this for you

@mixin multi-shadow($shadow-1, $shadow-2: false, $shadow-3: false, $shadow-4: false, $shadow-5: false, $shadow-6: false, $shadow-7: false, $shadow-8: false, $shadow-9: false) {
  $full: $shadow-1;
  @if $shadow-2 {
    $full: $full + "," + $shadow-2;
  }
  @if $shadow-3 {
    $full: $full + "," + $shadow-3;
  }
  @if $shadow-4 {
    $full: $full + "," + $shadow-4;
  }
  @if $shadow-5 {
    $full: $full + "," + $shadow-5;
  }
  @if $shadow-6 {
    $full: $full + "," + $shadow-6;
  }
  @if $shadow-7 {
    $full: $full + "," + $shadow-7;
  }
  @if $shadow-8 {
    $full: $full + "," + $shadow-8;
  }
  @if $shadow-9 {
    $full: $full + "," + $shadow-9;
  }
    
  -moz-box-shadow: $full;
  -webkit-box-shadow: $full;
  -o-box-shadow: $full;
  box-shadow: $full;
}

aah thank you, gbbowers!