Implement the comparison.

src/compare/macros.rs

@@ -1,6 +1,6 @@
 /// Create iterators for ast nodes where it only has to iterate over children
 macro_rules! compare_properties {
-    ($emacs:expr, $($emacs_field:expr),+) => {
+    ($emacs:expr, $($emacs_field:expr, $rust_value:expr, $compare_fn: ident),+) => {
         {
             let mut this_status = DiffStatus::Good;
             let mut message: Option<String> = None;
@@ -41,12 +41,29 @@ macro_rules! compare_properties {
             }
 
             $(
-            println!("{:?}", $emacs_field);
+            let emacs_name = match $emacs_field {
+                EmacsField::Required(name) => {
+                    name
+                },
+                EmacsField::Optional(name) => {
+                    name
+                },
+            };
+            let result = $compare_fn($emacs, emacs_name, $rust_value)?;
+            match result {
+                Some((DiffStatus::Good, _)) => unreachable!("No comparison functions should return Some() when DiffStatus is good."),
+                Some((status, msg)) => {
+                    this_status = status;
+                    message = msg;
+                },
+                _ => {}
+            }
             ),+
 
             match this_status {
                 DiffStatus::Good => {
-                    Ok(None)
+                    let result: Result<_, Box<dyn std::error::Error>> = Ok(None);
+                    result
                 },
                 _ => {
                     Ok(Some((this_status, message)))