cleanup, patterns

js-fp3/library/patterns.js

@@ -0,0 +1,10 @@
+export const match = (...branches) => (value) => {
+  for (const [predicate, handler] of branches) {
+    if (predicate(value)) return handler(value);
+  }
+  throw new Error('No matching pattern');
+};
+
+export const when = (predicate, handler) => [predicate, handler];
+
+export const any = () => true;