Use function pointers for iterators.

src/packages/array_basic.rs

@@ -120,8 +120,6 @@ def_package!(crate:BasicArrayPackage:"Basic array utilities.", lib, {
     // Register array iterator
     lib.set_iter(
         TypeId::of::<Array>(),
-        Box::new(|arr| Box::new(
-            arr.cast::<Array>().into_iter()) as Box<dyn Iterator<Item = Dynamic>>
-        ),
+        |arr| Box::new(arr.cast::<Array>().into_iter()) as Box<dyn Iterator<Item = Dynamic>>,
     );
 });

src/packages/iter_basic.rs

@@ -14,13 +14,10 @@ fn reg_range<T: Variant + Clone>(lib: &mut Module)
 where
     Range<T>: Iterator<Item = T>,
 {
-    lib.set_iter(
-        TypeId::of::<Range<T>>(),
-        Box::new(|source| {
-            Box::new(source.cast::<Range<T>>().map(|x| x.into_dynamic()))
-                as Box<dyn Iterator<Item = Dynamic>>
-        }),
-    );
+    lib.set_iter(TypeId::of::<Range<T>>(), |source| {
+        Box::new(source.cast::<Range<T>>().map(|x| x.into_dynamic()))
+            as Box<dyn Iterator<Item = Dynamic>>
+    });
 }
 
 fn get_range<T: Variant + Clone>(from: T, to: T) -> FuncReturn<Range<T>> {
@@ -58,13 +55,10 @@ where
     T: Variant + Clone + PartialOrd,
     StepRange<T>: Iterator<Item = T>,
 {
-    lib.set_iter(
-        TypeId::of::<StepRange<T>>(),
-        Box::new(|source| {
-            Box::new(source.cast::<StepRange<T>>().map(|x| x.into_dynamic()))
-                as Box<dyn Iterator<Item = Dynamic>>
-        }),
-    );
+    lib.set_iter(TypeId::of::<StepRange<T>>(), |source| {
+        Box::new(source.cast::<StepRange<T>>().map(|x| x.into_dynamic()))
+            as Box<dyn Iterator<Item = Dynamic>>
+    });
 }
 
 fn get_step_range<T>(from: T, to: T, step: T) -> FuncReturn<StepRange<T>>

src/packages/mod.rs

@@ -83,7 +83,7 @@ impl PackagesCollection {
         self.packages.iter().any(|p| p.contains_iter(id))
     }
     /// Get the specified TypeId iterator.
-    pub fn get_iter(&self, id: TypeId) -> Option<&IteratorFn> {
+    pub fn get_iter(&self, id: TypeId) -> Option<IteratorFn> {
         self.packages
             .iter()
             .map(|p| p.get_iter(id))