docs(examples): add some comments in the client example

examples/client.rs

@@ -11,6 +11,7 @@ use hyper::rt::{self, Future, Stream};
 fn main() {
     pretty_env_logger::init();
 
+    // Some simple CLI args requirements...
     let url = match env::args().nth(1) {
         Some(url) => url,
         None => {
@@ -19,6 +20,8 @@ fn main() {
         }
     };
 
+    // HTTPS requires picking a TLS implementation, so give a better
+    // warning if the user tries to request an 'https' URL.
     let url = url.parse::<hyper::Uri>().unwrap();
     if url.scheme_part().map(|s| s.as_ref()) != Some("http") {
         println!("This example only works with 'http' URLs.");
@@ -28,21 +31,29 @@ fn main() {
     rt::run(rt::lazy(move || {
         let client = Client::new();
 
-        let mut req = Request::new(Body::empty());
-        *req.uri_mut() = url;
+        client
+            // Fetch the url...
+            .get(url)
+            // And then, if we get a response back...
+            .and_then(|res| {
+                println!("Response: {}", res.status());
+                println!("Headers: {:#?}", res.headers());
 
-        client.request(req).and_then(|res| {
-            println!("Response: {}", res.status());
-            println!("Headers: {:#?}", res.headers());
-
-            res.into_body().for_each(|chunk| {
-                io::stdout().write_all(&chunk)
-                    .map_err(|e| panic!("example expects stdout is open, error={}", e))
+                // The body is a stream, and for_each returns a new Future
+                // when the stream is finished, and calls the closure on
+                // each chunk of the body...
+                res.into_body().for_each(|chunk| {
+                    io::stdout().write_all(&chunk)
+                        .map_err(|e| panic!("example expects stdout is open, error={}", e))
+                })
+            })
+            // If all good, just tell the user...
+            .map(|_| {
+                println!("\n\nDone.");
+            })
+            // If there was an error, let the user know...
+            .map_err(|err| {
+                eprintln!("Error {}", err);
             })
-        }).map(|_| {
-            println!("\n\nDone.");
-        }).map_err(|err| {
-            eprintln!("Error {}", err);
-        })
     }));
 }