Sass positioning mixin

sass-positioning-mixin.css

.element {
  top: 0;
  left: 1em;
  position: relative;
}

.other-element {
  top: 1em;
  right: 10%;
  position: fixed;
}

sass-positioning-mixin.sass

=position($position, $args)
  @each $o in top right bottom left
    $i: index($args, $o)
    @if $i and $i + 1 <= length($args) and type-of(nth($args, $i + 1)) == number
      #{$o}: nth($args, $i + 1)
  position: $position

=absolute($args)
  +position(absolute, $args)

=fixed($args)
  +position(fixed, $args)

=relative($args)
  +position(relative, $args)
  
// Usage
.element
  +relative(top 0 left 1em)

.other-element
  +fixed(top 1em left "WAT? A STRING?!" right 10% bottom)

sass-positioning-mixin.scss

/* SCSS code */

@mixin position($position, $args) {
  @each $o in top right bottom left {
    $i: index($args, $o);
 
    @if $i and $i + 1<= length($args) and type-of(nth($args, $i + 1)) == number  {
      #{$o}: nth($args, $i + 1);
    }
  }
  position: $position;
}
 
@mixin absolute($args) {
  @include position(absolute, $args);
}
 
@mixin fixed($args) {
  @include position(fixed, $args);
}
 
@mixin relative($args) {
  @include position(relative, $args);
}

/* Example Usage */

.element {
  @include relative(top 0 left 1em);
}
 
.other-element {
  @include fixed(top 1em left "WAT? A STRING?!" right 10% bottom)
}

Credit: http://www.sitepoint.com/sass-mixins-kickstart-project/