From 2386bcfe7f9973c8781c92b047fe085cd9b2b718 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Dominik=20Inf=C3=BChr?= <dominik.infuehr@gmail.com>
Date: Sat, 15 Feb 2025 10:19:05 +0100
Subject: [PATCH] frontend: Start with DoubleEndedIterator

---
 dora-frontend/src/traitdefck.rs | 14 ++++++++++++++
 pkgs/std/traits.dora            | 13 +++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/dora-frontend/src/traitdefck.rs b/dora-frontend/src/traitdefck.rs
index 2e9a99dfa..88e29cad8 100644
--- a/dora-frontend/src/traitdefck.rs
+++ b/dora-frontend/src/traitdefck.rs
@@ -610,4 +610,18 @@ mod tests {
             }
         ");
     }
+
+    #[test]
+    #[ignore]
+    fn assoc_type_of_super_trait() {
+        ok("
+            trait Foo {
+                type Item;
+            }
+
+            trait Bar: Foo {
+                fn f(): Self::Item;
+            }
+        ");
+    }
 }
diff --git a/pkgs/std/traits.dora b/pkgs/std/traits.dora
index 4546ba74f..3940ee1c8 100644
--- a/pkgs/std/traits.dora
+++ b/pkgs/std/traits.dora
@@ -169,6 +169,15 @@ pub trait Iterator {
     fn collect[T](): T where T: FromIterator[Self::Item] {
         T::fromIter[Self](self)
     }
+
+    @TraitObjectIgnore
+    fn rev(): Rev[Self] where Self: DoubleEndedIterator {
+        Rev[Self](self)
+    }
+}
+
+pub trait DoubleEndedIterator: Iterator {
+    // fn nextBack(): Option[Self::Item];
 }
 
 pub trait IntoIterator {
@@ -212,6 +221,10 @@ impl[I: Iterator, R] Iterator for Map[I, R] {
     }
 }
 
+pub class Rev[I: Iterator] {
+    it: I,
+}
+
 pub trait FromIterator[A] {
     static fn fromIter[T](iter: T): Self where T: Iterator[Item=A];
 }