Add functions and mixins to manipulate the utlities map

- get options, a specific option or a specific value for a given utility
- set options, new values or remove values for a given utility
- add or remove utilities

scss/mixins/_utilities.scss

@@ -95,3 +95,85 @@
     }
   }
 }
+
+// Helper functions and mixins for manipulating the utilities map
+
+// Gets the map of options for a given utility
+@function utilities-get-options($utility-name) {
+  @return map-get($utilities, $utility-name);
+}
+
+// Gets the value of a specific option for a given utility
+@function utilities-get-option($utility-name, $option-name) {
+  @return map-get(
+    utilities-get-options($utility-name),
+    $option-name
+  );
+}
+
+// Gets a specific value for the given utility
+@function utilities-get-value($utility-name, $value-name) {
+  @return map-get(
+    utility-get-option($utility-name, values),
+    $value-name
+  );
+}
+
+
+// Set options for a given utility, merged with the existing ones by default.
+// To completely replace the existing options, set the 3rd `$merge` parameter to false
+@mixin utilities-set-options($utility-name, $options, $merge: true) {
+
+  @if($merge) {
+    $options: map-merge(
+      utilities-get-options($utility-name),
+      $options
+    )
+  }
+
+  $utilities: map-merge($utilities,
+    $utility-name: $options
+  )
+}
+
+// Set a specific option to a new value for the given utility
+@mixin utilities-set-option($utility-name, $option-name, $value) {
+  @include utilities-set-options($utility-name, ($option-name: $value));
+}
+
+// Add new values to a given utility.
+// If you want to completely reconfigure the values
+// use `utility-set-option` to provide a new map
+// for the `values` option
+@mixin utilities-add-values($utility-name, $values) {
+  @include utilities-set-option(
+    $utility-name,
+    values,
+    map-merge(
+      utility-get-option($utility-name, values),
+      $values
+    )
+  )
+}
+
+// Remove specific values from a given utility
+@mixin utilities-remove-values($utility-name, $value-names...) {
+
+  $values: utility-get-option($utility-name, values);
+
+  $updated-values: map-remove($values, $value-names);
+
+  @include utility-set-option($utility-name, values, $updated-values);
+}
+
+// Add a new utility to the utilities map
+@mixin utilities-add($utility-name, $utility) {
+  $utilities: map-merge($utilities,
+    ($utility-name: $utility)
+  );
+}
+
+// Remove a utility from the utilities map
+@mixin utilities-remove($utility-names...) {
+  $utilities: map-remove($utility, $utility-names);
+}