$_name: null !global;
$_value: null !global;

// Custom loop to apply the name and value
@mixin _loop( $list, $responsive: true ) {
  @each $name, $value in $list {
    $_name: $name !global;
    $_value: $value !global;

    @content;

    $_name: null !global;
    $_value: null !global;
  }
}


// USE CASE

// You have variable for Padding classes, each item will become 5 classes covering all directions:
// p-x, pt-x, pr-x, pb-x, pl-x

$padding-classes: (
  05: 0.5rem,
  1: 1rem,
  15: 1.5rem,
  2: 2rem,
) !default;

@include _loop( $padding-classes ) {
  .p-#{ $_name } {
    padding: $_value;
  }

  .pt-#{ $_name } {
    padding-top: $_value;
  }

  .pr-#{ $_name } {
    padding-right: $_value;
  }

  .pb-#{ $_name } {
    padding-bottom: $_value;
  }

  .pl-#{ $_name } {
    padding-left: $_value;
  }
}

// The loop above will generate p-05, pt-05, pr-05, pb-05, pl-05, p-1, pt-1, and so on