add macros examples

macros/macros2.rs

@@ -0,0 +1,72 @@
+// Make me compile! Scroll down for hints :)
+
+fn main() {
+    my_macro!();
+}
+
+macro_rules! my_macro {
+    () => {
+        println!("Check out my macro!");
+    };
+}
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+// Macros don't quite play by the same rules as the rest of Rust, in terms of what's available
+// where.
+
+
+
+
+
+
+
+
+// Unlike other things in Rust, the order of "where you define a macro" versus "where you use it"
+// actually matters.