1 files changed, 48 insertions, 0 deletions
diff --git a/intl/icu_capi/src/properties_iter.rs b/intl/icu_capi/src/properties_iter.rs
new file mode 100644
index 0000000000..e0095789f5
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+++ b/intl/icu_capi/src/properties_iter.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 ).
+
+#[diplomat::bridge]
+pub mod ffi {
+    use alloc::boxed::Box;
+    use core::ops::RangeInclusive;
+
+    /// Result of a single iteration of [`CodePointRangeIterator`].
+    /// Logically can be considered to be an `Option<RangeInclusive<u32>>`,
+    ///
+    /// `start` and `end` represent an inclusive range of code points [start, end],
+    /// and `done` will be true if the iterator has already finished. The last contentful
+    /// iteration will NOT produce a range done=true, in other words `start` and `end` are useful
+    /// values if and only if `done=false`.
+    pub struct CodePointRangeIteratorResult {
+        pub start: u32,
+        pub end: u32,
+        pub done: bool,
+    }
+
+    /// An iterator over code point ranges, produced by `ICU4XCodePointSetData` or
+    /// one of the `ICU4XCodePointMapData` types
+    #[diplomat::opaque]
+    pub struct CodePointRangeIterator<'a>(pub Box<dyn Iterator<Item = RangeInclusive<u32>> + 'a>);
+
+    impl<'a> CodePointRangeIterator<'a> {
+        /// Advance the iterator by one and return the next range.
+        ///
+        /// If the iterator is out of items, `done` will be true
+        #[allow(clippy::should_implement_trait)] // Rust isn't calling this code
+        pub fn next(&mut self) -> CodePointRangeIteratorResult {
+            self.0
+                .next()
+                .map(|r| CodePointRangeIteratorResult {
+                    start: *r.start(),
+                    end: *r.end(),
+                    done: false,
+                })
+                .unwrap_or(CodePointRangeIteratorResult {
+                    start: 0,
+                    end: 0,
+                    done: true,
+                })
+        }
+    }
+}