Streamline code

src/core/collection/merge.rs

@@ -86,17 +86,19 @@ pub trait WithId {
     fn id(&self) -> &Self::Id;
 }
 
-pub struct MergeCollections<ID, T> {
+pub struct MergeCollections<ID, T, IT> {
     _id: PhantomData<ID>,
     _t: PhantomData<T>,
+    _it: PhantomData<IT>,
 }
 
-impl<ID, T> MergeCollections<ID, T>
+impl<ID, T, IT> MergeCollections<ID, T, IT>
 where
     ID: Eq + Hash + Clone,
     T: WithId<Id = ID> + Merge + Ord,
+    IT: IntoIterator<Item = T>,
 {
-    pub fn merge_iter<IT: IntoIterator<Item = T>>(primary: IT, secondary: IT) -> Vec<T> {
+    pub fn merge_iter(primary: IT, secondary: IT) -> Vec<T> {
         let primary = primary
             .into_iter()
             .map(|item| (item.id().clone(), item))
@@ -104,7 +106,7 @@ where
         Self::merge(primary, secondary)
     }
 
-    pub fn merge<IT: IntoIterator<Item = T>>(mut primary: HashMap<ID, T>, secondary: IT) -> Vec<T> {
+    pub fn merge(mut primary: HashMap<ID, T>, secondary: IT) -> Vec<T> {
         for secondary_item in secondary {
             if let Some(ref mut primary_item) = primary.get_mut(secondary_item.id()) {
                 primary_item.merge_in_place(secondary_item);