this works, but without reference, this moves ownership so can only be

called once

src/main.rs

@@ -1,6 +1,8 @@
-fn main() {
+fn say_hello(name: String) {
-    let s1 = String::from("hello");
+    println!("{}", name);
-    let s2 = s1;
+}
-    println!("{}", s2);
+
-    //println!("{}", s1);
+fn main() {
+    let name = String::from("alice");
+    say_hello(name);
 }