tuple lookup function for scss

_lookup.scss

@function lookup ($targetKey, $map, $index:2, $default:'') {
  @each $entry in $map {
    @if length($entry) >= $index {
        $key: nth($entry, 1);
        $value: nth($entry, $index);
        @if $key == $targetKey {
          @return $value;
        }
    }
  }
  @return $default;
}

$example-tuple: 
  key1 white,
  key2 black #202020
;

.usage {
  color: lookup(key1, $example-tuple);
  background-color: lookup(key2, $example-tuple, 3);
}