refactor: restructured logic revalidation example to show types clearly

examples/core/state_generation/src/templates/revalidation.rs

@@ -22,7 +22,7 @@ pub fn get_template<G: Html>() -> Template<G> {
         // load this page. For that reason, this should NOT do long-running work, as requests will be delayed. If both this
         // and `revaldiate_after()` are provided, this logic will only run when `revalidate_after()` tells Perseus
         // that it should revalidate.
-        .should_revalidate_fn(|| async { Ok(true) })
+        .should_revalidate_fn(should_revalidate)
         .build_state_fn(get_build_state)
 }
 
@@ -33,3 +33,10 @@ pub async fn get_build_state(_path: String, _locale: String) -> RenderFnResultWi
         time: format!("{:?}", std::time::SystemTime::now()),
     })
 }
+
+// This will run every time `.revalidate_after()` permits the page to be revalidated
+// This acts as a secondary check, and can perform arbitrary logic to check if we should actually revalidate a page
+pub async fn should_revalidate() -> RenderFnResultWithCause<bool> {
+    // For simplicity's sake, this will always say we should revalidate, but you could amke this check any condition
+    Ok(true)
+}