Refining Ch06.

projects/option_demo/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "option_demo"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]

projects/option_demo/src/main.rs

@@ -0,0 +1,6 @@
+fn main() {
+    let x: i8 = 5;
+    let y: Option<i8> = Some(5);
+
+    let sum = x + y;
+}