Introduce pinned_async macro

src/main.rs

@@ -48,9 +48,10 @@ fn show_window ( application : & Application ) {
 
 				let ui = UI :: new (
 					window ,
-					|film_uuid| Box :: pin ( async {
+					|film_uuid| pinned_async ! {
-						data_manager . get_film_details (film_uuid) . await . unwrap ()
+						data_manager . get_film_details (film_uuid) . await
-					} ) ,
+							. expect ("A film with the given UUID should exist")
+					} ,
 				) ;
 				window . show () ;
 

src/utility.rs

@@ -5,3 +5,15 @@ pub fn leak < 'l , Type > ( inner : Type ) -> & 'l Type {
 pub fn leak_mut < 'l , Type > ( inner : Type ) -> & 'l mut Type {
 	Box :: leak ( Box :: new (inner) )
 }
+
+macro_rules ! pinned_async { (
+	$ ( $ async_expression : expr ) ; +
+) => {
+	Box :: pin ( async {
+		$ ( $ async_expression ) ; +
+	} )
+} }
+
+
+
+pub (crate) use pinned_async ;