Auto merge of #106193 - compiler-errors:rollup-0l54wka, r=compiler-errors

Rollup of 9 pull requests

Successful merges:

 - #103718 (More inference-friendly API for lazy)
 - #105765 (Detect likely `.` -> `..` typo in method calls)
 - #105852 (Suggest rewriting a malformed hex literal if we expect a float)
 - #105965 (Provide local extern function arg names)
 - #106064 (Partially fix `explicit_outlives_requirements` lint in macros)
 - #106179 (Fix a formatting error in Iterator::for_each docs)
 - #106181 (Fix doc comment parsing description in book)
 - #106187 (Update the documentation of `Vec` to use `extend(array)` instead of `extend(array.iter().copied())`)
 - #106189 (Fix UnsafeCell Documentation Spelling Error)

Failed merges:

r? `@ghost`
`@rustbot` modify labels: rollup

2 files changed, 7 insertions, 4 deletions

diff --git a/library/std/src/sync/lazy_lock.rs b/library/std/src/sync/lazy_lock.rs
index c8d3289ca4a..bf5a716fa03 100644
--- a/library/std/src/sync/lazy_lock.rs
+++ b/library/std/src/sync/lazy_lock.rs
@@ -46,17 +46,14 @@ pub struct LazyLock<T, F = fn() -> T> {
     cell: OnceLock<T>,
     init: Cell<Option<F>>,
 }
-
-impl<T, F> LazyLock<T, F> {
+impl<T, F: FnOnce() -> T> LazyLock<T, F> {
     /// Creates a new lazy value with the given initializing
     /// function.
     #[unstable(feature = "once_cell", issue = "74465")]
     pub const fn new(f: F) -> LazyLock<T, F> {
         LazyLock { cell: OnceLock::new(), init: Cell::new(Some(f)) }
     }
-}
 
-impl<T, F: FnOnce() -> T> LazyLock<T, F> {
     /// Forces the evaluation of this lazy value and
     /// returns a reference to result. This is equivalent
     /// to the `Deref` impl, but is explicit.
diff --git a/library/std/src/sync/lazy_lock/tests.rs b/library/std/src/sync/lazy_lock/tests.rs
index f11b66bfca5..a5d4e25c596 100644
--- a/library/std/src/sync/lazy_lock/tests.rs
+++ b/library/std/src/sync/lazy_lock/tests.rs
@@ -136,6 +136,12 @@ fn sync_lazy_poisoning() {
     }
 }
 
+// Check that we can infer `T` from closure's type.
+#[test]
+fn lazy_type_inference() {
+    let _ = LazyCell::new(|| ());
+}
+
 #[test]
 fn is_sync_send() {
     fn assert_traits<T: Send + Sync>() {}