planning

node_modules/@mapbox/mapbox-gl-style-spec/util/result.js

@@ -0,0 +1,19 @@
+// @flow
+
+/**
+ * A type used for returning and propagating errors. The first element of the union
+ * represents success and contains a value, and the second represents an error and
+ * contains an error value.
+ * @private
+ */
+export type Result<T, E> =
+    | {| result: 'success', value: T |}
+    | {| result: 'error', value: E |};
+
+export function success<T, E>(value: T): Result<T, E> {
+    return {result: 'success', value};
+}
+
+export function error<T, E>(value: E): Result<T, E> {
+    return {result: 'error', value};
+}