From: Ian Jackson <ijackson@chiark.greenend.org.uk>
Date: Thu, 14 Nov 2024 20:41:50 +0000 (+0000)
Subject: better
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ian/git?a=commitdiff_plain;h=8ae8a4d66f2ba2f2df13a759c4445cc799237d7a;p=manually-boxed

better
---

diff --git a/src/lib.rs b/src/lib.rs
index c651a81..444317a 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -31,8 +31,8 @@ pub unsafe trait IsRefToken<'a>: Sized {
 pub unsafe trait IsMutToken<'a>: IsRefToken<'a> + Sized {
     /// Obtain a new ZST token from something that might be a real object.
     #[inline]
-    fn mut_token<'r, 's>(mut self) -> MutToken<'r>
-    where 's: 'r, 'a: 'r,
+    fn mut_token<'r>(mut self) -> MutToken<'r>
+    where 'a: 'r,
     {
         MutToken(PhantomData)
     }
@@ -451,6 +451,7 @@ mod tests {
     #[test]
     fn demo() {
         use list::{List, HeadAndTail};
+        use HeadAndTail as H;
 
         let s = |s: &str| format!("{s}");
 
@@ -460,10 +461,13 @@ mod tests {
         drop(l);
 
         let mut l = List::new();     l.check_consistency();
-        assert_eq!(l.head_and_tail_mut(), HeadAndTail::None);
+        assert_eq!(l.head_and_tail_mut(), H::None);
 
         l.append(s("hi"));           l.check_consistency();
+        assert_eq!(l.head_and_tail_mut(), H::One(&mut s("hi")));
+
         l.append(s("ho"));           l.check_consistency();
+        assert_eq!(l.head_and_tail_mut(), H::Both(&mut s("hi"), &mut s("ho")));
 
         write!(l.front_mut().unwrap(), "!").unwrap();
         assert_eq!(l.pop_front(), Some(s("hi!")));  l.check_consistency();