perf: optimize page map iterator to avoid items copying (#329)

algolia · Nov 18, 2024 · d3eff80 · d3eff80
1 parent 1a1e21e
commit d3eff80
Showing 1 changed file with 5 additions and 4 deletions.
diff --git a/Sources/InstantSearchCore/Pagination/PageMap.swift b/Sources/InstantSearchCore/Pagination/PageMap.swift
@@ -82,15 +82,16 @@ struct PageMap<Item> {
 // MARK: SequenceType
 
 extension PageMap: Sequence {
-  public func makeIterator() -> IndexingIterator<[Item?]> {
-    let elements = (self.startIndex..<self.endIndex).map { self[$0] }
-    return IndexingIterator(_elements: elements)
+  public func makeIterator() -> IndexingIterator<Self> {
+    return IndexingIterator(_elements: self)
   }
 }
 
 // MARK: CollectionType
 
 extension PageMap: BidirectionalCollection {
+  public typealias Element = Item?
+
   public typealias Index = Int
 
   public var startIndex: Index { return 0 }
@@ -114,7 +115,7 @@ extension PageMap: BidirectionalCollection {
 
   /// Accesses and sets elements for a given flat index position.
   /// Currently, setter can only be used to replace non-optional values.
-  public subscript(position: Index) -> Item? {
+  public subscript(position: Index) -> Element {
     get {
       let pageIndex = self.pageIndex(for: position)
       let inPageIndex = position % pageSize