adding opposite direction function to return the opposite direction of each direction in a list

opentech/static_src/src/sass/apply/abstracts/_functions.scss

+// Returns the opposite direction of each direction in a list
+// @param {List} $directions - List of initial directions
+// @return {List} - List of opposite directions
+@function opposite-direction($directions) {
+    $opposite-directions: ();
+    $direction-map: (
+        'top':    'bottom',
+        'right':  'left',
+        'bottom': 'top',
+        'left':   'right',
+        'center': 'center',
+        'ltr':    'rtl',
+        'rtl':    'ltr'
+    );
+
+    @each $direction in $directions {
+        $direction: to-lower-case($direction);
+
+        @if map-has-key($direction-map, $direction) {
+            $opposite-directions: append($opposite-directions, unquote(map-get($direction-map, $direction)));
+        } @else {
+            @warn 'No opposite direction can be found for `#{$direction}`. Direction omitted.';
+        }
+    }
+    @return $opposite-directions;
+}

opentech/static_src/src/sass/apply/main.scss

@@ -2,6 +2,7 @@
 @import 'vendor/normalize';
 
 // Abstracts
+@import 'abstracts/functions';
 @import 'abstracts/mixins';
 @import 'abstracts/variables';