flow all the things

src/example.js

@@ -7,5 +7,4 @@ if (!('serviceWorker' in navigator)) {
 
 const greeting = 'hello'
 console.log(`${greeting} world!`)
-
 ;[(1, 2, 3)].forEach(x => console.log(x))

src/flow-example.js

@@ -0,0 +1,22 @@
+// @flow
+function add(a: number, b: number): number {
+  return a + b
+}
+
+type User = {
+  name: {
+    first: string,
+    middle: string,
+    last: string,
+  },
+}
+function getFullName(user: User): string {
+  const {
+    name: {first, middle, last},
+  } = user
+  return [first, middle, last].filter(Boolean).join('')
+}
+
+add(1, 2)
+
+getFullName({name: {first: 'Joe', middle: 'Bud', last: 'Matthews'}})