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diff --git a/third_party/rust/litemap/src/databake.rs b/third_party/rust/litemap/src/databake.rs
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+++ b/third_party/rust/litemap/src/databake.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 ).
+
+use crate::LiteMap;
+use databake::*;
+
+/// Bakes a LiteMap into Rust code for fast runtime construction from data. Use this impl during
+/// code generation, such as in a `build.rs` script.
+///
+/// For the most efficient bake, bake the [`LiteMap`] with a slice store. Use functions such as
+/// the following for converting an allocated [`LiteMap`] to a borrowing [`LiteMap`]:
+///
+/// - [`LiteMap::to_borrowed_keys()`]
+/// - [`LiteMap::to_borrowed_values()`]
+/// - [`LiteMap::to_borrowed_keys_values()`]
+/// - [`LiteMap::as_sliced()`]
+///
+/// # Examples
+///
+/// ```
+/// use databake::*;
+/// use litemap::LiteMap;
+///
+/// // Construct the LiteMap fully owned and allocated:
+/// let mut litemap_alloc: LiteMap<usize, String, Vec<_>> = LiteMap::new_vec();
+/// litemap_alloc.insert(1usize, "one".to_string());
+/// litemap_alloc.insert(2usize, "two".to_string());
+/// litemap_alloc.insert(10usize, "ten".to_string());
+///
+/// // Convert to a borrowed type for baking:
+/// let litemap_str: LiteMap<usize, &str, Vec<_>> =
+///     litemap_alloc.to_borrowed_values();
+/// let litemap_slice: LiteMap<usize, &str, &[_]> = litemap_str.as_sliced();
+///
+/// // The bake will now work for const construction:
+/// let mut ctx = Default::default();
+/// println!(
+///     "const FOO: LiteMap<usize, &str, &[(usize, &str)]> = {};",
+///     litemap_slice.bake(&mut ctx)
+/// );
+/// ```
+impl<K, V, S> Bake for LiteMap<K, V, S>
+where
+    S: Bake,
+{
+    fn bake(&self, env: &CrateEnv) -> TokenStream {
+        env.insert("litemap");
+        let store = self.values.bake(env);
+        quote! { litemap::LiteMap::from_sorted_store_unchecked(#store) }
+    }
+}
+
+#[test]
+fn test_baked_map() {
+    // Const construction:
+    test_bake!(
+        LiteMap<usize, &str, &[(usize, &str)]>,
+        const: crate::LiteMap::from_sorted_store_unchecked(
+                &[
+                    (1usize, "one"),
+                    (2usize, "two"),
+                    (10usize, "ten")
+                ]
+            ),
+        litemap
+    );
+    // Non-const construction:
+    test_bake!(
+        LiteMap<usize, String, Vec<(usize, String)>>,
+        crate::LiteMap::from_sorted_store_unchecked(
+                alloc::vec![
+                    (1usize, "one".to_owned()),
+                    (2usize, "two".to_owned()),
+                    (10usize, "ten".to_owned()),
+                ]
+            ),
+        litemap
+    );
+}