add notes: iterators, io,

training-slides/src/io.md

@@ -135,6 +135,10 @@ fn main() -> std::io::Result<()> {
 * When do you hit the end of a `TcpStream`?
   * When either side does a `shutdown`
 
+Note:
+
+* `Read` trait has a method `read_to_end()`
+
 ## Binding Ports
 
 * `TcpListener` needs to know which IP address and port to bind
@@ -156,6 +160,14 @@ fn main() -> Result<(), std::io::Error> {
 * [`SocketAddr`](https://doc.rust-lang.org/std/net/enum.SocketAddr.html) is an enum of [`SocketAddrV4`](https://doc.rust-lang.org/std/net/struct.SocketAddrV4.html) and [`SocketAddrV6`](https://doc.rust-lang.org/std/net/struct.SocketAddrV6.html)
 * But TLS, HTTP and QUIC are all third-party crates
 
+Note:
+
+Some current prominent examples of each -
+
+* TLS - [RusTLS](https://github.com/rustls/rustls)
+* HTTP - [hyperium/http](https://github.com/hyperium/http)
+* QUIC - [cloudflare/quiche](https://github.com/cloudflare/quiche)
+
 ## Failures
 
 * Almost any I/O operation can fail

training-slides/src/iterators.md

@@ -22,6 +22,13 @@ To *iterate* in Rust is to produce a sequence of items, one at a time.
 * Some *Iterators* will calculate each item on-the-fly
 * Some *Iterators* will take data another iterator, and then calculate something new
 
+Note:
+
+Technically, all iterators calculate things on-the-fly. Some own another iterator and use that as input to their calculation, and some have an internal state that they can use for calculation. `fn next(&mut self) -> Self::Item` can only access `Self` so it is about what `Self` contains.
+
+* `struct SomeIter<T> where T: Iterator { inner: T }`
+* `struct SomeOtherIter { random_seed: u32 }`
+
 ## Important to note
 
 * Iterators are lazy