Expand on readme...

Author: rklaehn

README.md

@@ -7,17 +7,35 @@ It only works with enums where each variant has a single unnamed element, and if
 The most basic use is to provide conversions between the enum cases and the enum type itself. You could achieve something similar with the popular [derive_more] crate.
 
 ```rust
-# struct PutRequest;
-# struct GetRequest;
 #[enum_conversions()]
-enum Protocol {
+enum Request {
   Get(GetRequest),
   Put(PutRequest),
 }
 ```
 
 A more advanced use, and the reason for this crate to exist, is to provide conversions between enum variants and any type that itself has a *conversion* to the enum. This allows to use nested enums, like you would in a complex protocol that has several subsystems.
 
+```rust
+#[enum_conversions(Request)]
+enum StoreRequest {
+  Get(GetRequest),
+  Put(PutRequest),
+}
+
+#[enum_conversions(Request)]
+enum NetworkRequest {
+  Ping(PingRequest),
+}
+
+#[enum_conversions()]
+enum Request {
+  Store(StoreRequest),
+  Network(NetworkRequest),
+}
+```
+
+Here we define conversions from `GetRequest` to `StoreRequest`, from `StoreRequest` to `Request`, and then directly from `GetRequest` to `Request`, and corresponding [TryFrom] conversions in the other direction.
 
 ## Generated conversions