loop-through-array.sass

$direction-list: left right center

@each $direction in $direction-list
  $i: index($direction-list, $direction) //only needed if you need an index

  .align-#{$direction}
    text-align: $direction


// And as a Key/Value thing (helpful if you use the same word but one needs to be treated as a variable)
$background-list: geyser $geyser, smaltblue $smaltblue, salmon $salmon

@each $background in $background-list
  $key: nth($background, 1);
  $value: nth($background, 2);

  .bg-#{$key}
    background-color: $value