Minor code cleanup.

src/builtin.rs

@@ -580,7 +580,7 @@ impl Engine<'_> {
         }
 
         fn range<T>(from: T, to: T) -> Range<T> {
-            (from..to)
+            from..to
         }
 
         reg_iterator::<INT>(self);
@@ -773,9 +773,12 @@ impl Engine<'_> {
             self.register_dynamic_fn("pop", |list: &mut Array| {
                 list.pop().unwrap_or_else(|| ().into_dynamic())
             });
-            self.register_dynamic_fn("shift", |list: &mut Array| match list.len() {
+            self.register_dynamic_fn("shift", |list: &mut Array| {
-                0 => ().into_dynamic(),
+                if !list.is_empty() {
-                _ => list.remove(0),
+                    ().into_dynamic()
+                } else {
+                    list.remove(0)
+                }
             });
             self.register_fn("len", |list: &mut Array| list.len() as INT);
             self.register_fn("clear", |list: &mut Array| list.clear());

src/fn_register.rs

@@ -196,13 +196,10 @@ macro_rules! def_register {
 
                     // Call the user-supplied function using ($clone) to
                     // potentially clone the value, otherwise pass the reference.
-                    match f($(($clone)($par)),*) {
+                    f($(($clone)($par)),*).map(|r| Box::new(r) as Dynamic).map_err(|mut err| {
-                        Ok(r) => Ok(Box::new(r) as Dynamic),
+                        err.set_position(pos);
-                        Err(mut err) => {
+                        err
-                            err.set_position(pos);
+                    })
-                            Err(err)
-                        }
-                    }
                 };
                 self.register_fn_raw(name, Some(vec![$(TypeId::of::<$par>()),*]), Box::new(fun));
             }