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diff --git a/vendor/icu_locid/src/ordering.rs b/vendor/icu_locid/src/ordering.rs
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+++ b/vendor/icu_locid/src/ordering.rs
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+// This file is part of ICU4X. For terms of use, please see the file
+// called LICENSE at the top level of the ICU4X source tree
+// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
+
+//! Utilities for performing ordering operations on locales.
+
+use core::cmp::Ordering;
+
+/// The result of a subtag iterator comparison operation.
+///
+/// See [`Locale::strict_cmp_iter`].
+///
+/// # Examples
+///
+/// Check whether a stream of subtags contains two expected locales back-to-back:
+///
+/// ```
+/// use icu::locid::{locale, Locale, SubtagOrderingResult};
+/// use std::cmp::Ordering;
+///
+/// let subtags = b"en-US-it-IT".split(|b| *b == b'-');
+/// let locales = [locale!("en-US"), locale!("it-IT")];
+/// let mut result = SubtagOrderingResult::Subtags(subtags);
+/// for loc in locales.iter() {
+///     match result {
+///         SubtagOrderingResult::Subtags(it) => {
+///             result = loc.strict_cmp_iter(it);
+///         }
+///         SubtagOrderingResult::Ordering(ord) => break,
+///     }
+/// }
+///
+/// assert_eq!(Ordering::Equal, result.end());
+/// ```
+///
+/// [`Locale::strict_cmp_iter`]: crate::Locale::strict_cmp_iter
+#[allow(clippy::exhaustive_enums)] // well-defined exhaustive enum semantics
+pub enum SubtagOrderingResult<I> {
+    /// Potentially remaining subtags after the comparison operation.
+    Subtags(I),
+    /// Resolved ordering between the locale object and the subtags.
+    Ordering(Ordering),
+}
+
+impl<I> SubtagOrderingResult<I>
+where
+    I: Iterator,
+{
+    /// Invoke this function if there are no remaining locale objects to chain in order to get
+    /// a fully resolved [`Ordering`].
+    #[inline]
+    pub fn end(self) -> Ordering {
+        match self {
+            Self::Subtags(mut it) => match it.next() {
+                Some(_) => Ordering::Less,
+                None => Ordering::Equal,
+            },
+            Self::Ordering(o) => o,
+        }
+    }
+}