Put everything in src directories

packages/lib/src/Deferred.ts

@@ -0,0 +1,14 @@
+export type Deferred<T> = Promise<T> & {
+  resolve: (arg: T) => void
+  reject: (arg: T) => void
+}
+
+export const defer = <T>(): Deferred<T> => {
+  let resolve, reject
+  const p = new Promise((resolve_, reject_) => {
+    resolve = resolve_
+    reject = reject_
+  })
+
+  return (Object.assign(p, {resolve, reject}) as unknown) as Deferred<T>
+}