Moved include into router.

src/router.rs

@@ -0,0 +1,34 @@
+#[derive(Clone, Debug, Eq, Hash)]
+pub enum Include<T> {
+    All,
+    Just(T),
+}
+
+impl<T: PartialEq> PartialEq for Include<T> {
+    fn eq(&self, other: &Self) -> bool {
+        match self {
+            Include::All => true,
+            Include::Just(data) => match other {
+                Include::All => true,
+                Include::Just(other_data) => data == other_data,
+            },
+        }
+    }
+}
+
+#[cfg(test)]
+mod includes {
+    use super::*;
+
+    #[test]
+    fn does_all_equal_evberything() {
+        let a: Include<isize> = Include::All;
+        let b: Include<isize> = Include::Just(5);
+        let c: Include<isize> = Include::Just(7);
+        assert!(a == a, "all should equal all");
+        assert!(a == b, "all should equal some");
+        assert!(b == a, "some should equal all");
+        assert!(b == b, "same some should equal");
+        assert!(b != c, "different somes do not equal");
+    }
+}