From 4e0af7cc6176b7410fa95c3324381c2baa9ad769 Mon Sep 17 00:00:00 2001
From: Oli Scherer <git-spam-no-reply9815368754983@oli-obk.de>
Date: Mon, 10 Jun 2024 16:17:38 +0000
Subject: [PATCH] Require any function with a tait in its signature to actually
 constrain a hidden type

---
 example/issue-72793.rs | 23 +++++++++++++----------
 1 file changed, 13 insertions(+), 10 deletions(-)

diff --git a/example/issue-72793.rs b/example/issue-72793.rs
index 166b0060043..2e08fbca8ef 100644
--- a/example/issue-72793.rs
+++ b/example/issue-72793.rs
@@ -2,20 +2,23 @@
 
 #![feature(type_alias_impl_trait)]
 
-trait T {
-    type Item;
-}
+mod helper {
+    pub trait T {
+        type Item;
+    }
 
-type Alias<'a> = impl T<Item = &'a ()>;
+    pub type Alias<'a> = impl T<Item = &'a ()>;
 
-struct S;
-impl<'a> T for &'a S {
-    type Item = &'a ();
-}
+    struct S;
+    impl<'a> T for &'a S {
+        type Item = &'a ();
+    }
 
-fn filter_positive<'a>() -> Alias<'a> {
-    &S
+    pub fn filter_positive<'a>() -> Alias<'a> {
+        &S
+    }
 }
+use helper::*;
 
 fn with_positive(fun: impl Fn(Alias<'_>)) {
     fun(filter_positive());