[ SASS ] position指定用のmixin

abs == absolute
fixed == fixed
それ以外はrelativeの扱いにします。
数値は top, right, bottom, left の順に。

##mixin

_mixin.scss

// position:
// ---------------------------------------- //
@mixin position($def: relative, $t: auto, $r: auto, $b: auto, $l: auto){
	@if $def == abs {
        position: absolute;
    } @else if $def == fixed {
        position: fixed;
    } @else {
        position: relative;
    }
	@if $t != auto and $t != n { top: $t; }
	@if $r != auto and $r != n { right: $r };
	@if $b != auto and $b != n { bottom: $b };
	@if $l != auto and $l != n { left: $l };
}

// @include position;
// -> position: relative;

// @include position(abs);
// -> position: absolute;

// @include position(fixed, 0, n, n, 0);
// -> position: fixed;
//    top: 0;
//    left: 0;

##SCSS

example.scss

.example {
	@include position(absolute, 20px, n, n, 55px);
}

##CSS

example.css

.example {
	position: absolute;
	top: 20px;
	left: 55px;
}