Make some `Clone` impls `const`

[rust.git] / library / core / src / option.rs

diff --git a/library/core/src/option.rs b/library/core/src/option.rs
index 4eeb5e43943862dd7d7f9a57d5d3dc49a3db51c6..941d7e07926281ebf5e47fc3ebaed21ded4d20c8 100644 (file)
--- a/library/core/src/option.rs
+++ b/library/core/src/option.rs
@@ -703,7 +703,8 @@ pub fn as_pin_mut(self: Pin<&mut Self>) -> Option<Pin<&mut T>> {
     #[inline]
     #[track_caller]
     #[stable(feature = "rust1", since = "1.0.0")]
-    pub fn expect(self, msg: &str) -> T {
+    #[rustc_const_unstable(feature = "const_option", issue = "67441")]
+    pub const fn expect(self, msg: &str) -> T {
         match self {
             Some(val) => val,
             None => expect_failed(msg),
@@ -1658,7 +1659,7 @@ pub const fn transpose(self) -> Result<Option<T>, E> {
 #[inline(never)]
 #[cold]
 #[track_caller]
-fn expect_failed(msg: &str) -> ! {
+const fn expect_failed(msg: &str) -> ! {
     panic!("{}", msg)
 }
 
@@ -1667,7 +1668,11 @@ fn expect_failed(msg: &str) -> ! {
 /////////////////////////////////////////////////////////////////////////////
 
 #[stable(feature = "rust1", since = "1.0.0")]
-impl<T: Clone> Clone for Option<T> {
+#[rustc_const_unstable(feature = "const_clone", issue = "91805")]
+impl<T> const Clone for Option<T>
+where
+    T: ~const Clone + ~const Drop,
+{
     #[inline]
     fn clone(&self) -> Self {
         match self {
@@ -2088,6 +2093,11 @@ fn from_residual(residual: Option<convert::Infallible>) -> Self {
     }
 }
 
+#[unstable(feature = "try_trait_v2_residual", issue = "91285")]
+impl<T> ops::Residual<T> for Option<convert::Infallible> {
+    type TryType = Option<T>;
+}
+
 impl<T> Option<Option<T>> {
     /// Converts from `Option<Option<T>>` to `Option<T>`.
     ///