Added filename to top of .rs files

macros/macros1.rs

@@ -1,3 +1,4 @@
+// macros1.rs
 // Make me compile! Scroll down for hints :)
 
 macro_rules! my_macro {

macros/macros2.rs

@@ -1,3 +1,4 @@
+// macros2.rs
 // Make me compile! Scroll down for hints :)
 
 fn main() {

macros/macros3.rs

@@ -1,3 +1,4 @@
+// macros3.rs
 // Make me compile, without taking the macro out of the module! Scroll down for hints :)
 
 mod macros {

macros/macros4.rs

@@ -1,3 +1,4 @@
+// macros4.rs
 // Make me compile! Scroll down for hints :)
 
 macro_rules! my_macro {