fix: filter takes snapshot iterator item

starkware-libs · Jan 28, 2025 · 695f5d2 · 695f5d2
1 parent d439c1d
commit 695f5d2
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Showing 3 changed files with 6 additions and 8 deletions.
diff --git a/corelib/src/iter/adapters/filter.cairo b/corelib/src/iter/adapters/filter.cairo
@@ -19,10 +19,9 @@ pub impl FilterIterator<
     I,
     P,
     impl TIter: Iterator<I>,
-    +core::ops::Fn<P, (TIter::Item,)>[Output: bool],
+    +core::ops::Fn<P, (@TIter::Item,)>[Output: bool],
     +Destruct<I>,
     +Destruct<P>,
-    +Copy<TIter::Item>,
     +Copy<P>,
     +Destruct<TIter::Item>,
 > of Iterator<Filter<I, P>> {

diff --git a/corelib/src/iter/traits/iterator.cairo b/corelib/src/iter/traits/iterator.cairo
@@ -1,5 +1,5 @@
 use crate::iter::adapters::{
-    Enumerate, Filter, Map, Zip, enumerated_iterator, filter_iterator, mapped_iterator,
+    Enumerate, Filter, Map, Peekable, Zip, enumerated_iterator, filter_iterator, mapped_iterator,
     peekable_iterator, zipped_iterator,
 };
 use crate::iter::traits::{Product, Sum};
@@ -388,7 +388,7 @@ pub trait Iterator<T> {
     }
 
     /// Creates an iterator which uses a closure to determine if an element
-    /// should be yielded.
+    /// should be yielded. The closure takes each element as a snapshot.
     ///
     /// Given an element the closure must return `true` or `false`. The returned
     /// iterator will yield only the elements for which the closure returns
@@ -401,7 +401,7 @@ pub trait Iterator<T> {
     /// ```
     /// let a = array![0_u32, 1, 2];
     ///
-    /// let mut iter = a.into_iter().filter(|x| x > 0);
+    /// let mut iter = a.into_iter().filter(|x| *x > 0);
     ///
     /// assert_eq!(iter.next(), Option::Some(1));
     /// assert_eq!(iter.next(), Option::Some(2));
@@ -412,10 +412,9 @@ pub trait Iterator<T> {
     #[inline]
     fn filter<
         P,
-        +core::ops::Fn<P, (Self::Item,)>[Output: bool],
+        +core::ops::Fn<P, (@Self::Item,)>[Output: bool],
         +Destruct<P>,
         +Destruct<T>,
-        +Copy<Self::Item>,
         +Destruct<Self::Item>,
     >(
         self: T, predicate: P,

diff --git a/corelib/src/test/iter_test.cairo b/corelib/src/test/iter_test.cairo
@@ -124,7 +124,7 @@ fn test_iter_find() {
 
 #[test]
 fn test_iter_adapter_filter() {
-    let mut iter = array![0_u32, 1, 2].into_iter().filter(|x| x > 0);
+    let mut iter = array![0_u32, 1, 2].into_iter().filter(|x| *x > 0);
     assert_eq!(iter.next(), Option::Some(1));
     assert_eq!(iter.next(), Option::Some(2));
     assert_eq!(iter.next(), Option::None);