Rollup merge of rust-lang#147246 - Kivooeo:btree-map-split-off-doc, r=Mark-Simulacrum

matthiaskrgr · web-flow · commit b96bd11c549d · 2025-10-12T10:13:15.000+02:00
Explain not existed key in BTreeMap::split_off Fixes rust-lang#147174 r? libs
diff --git a/library/alloc/src/collections/btree/map.rs b/library/alloc/src/collections/btree/map.rs
@@ -1368,7 +1368,8 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {
     }
 
     /// Splits the collection into two at the given key. Returns everything after the given key,
-    /// including the key.
+    /// including the key. If the key is not present, the split will occur at the nearest
+    /// greater key, or return an empty map if no such key exists.
     ///
     /// # Examples
     ///

Original file line number	Diff line number	Diff line change
`@@ -1368,7 +1368,8 @@ impl<K, V, A: Allocator + Clone> BTreeMap<K, V, A> {`
`1368`	`1368`	`}`
`1369`	`1369`
`1370`	`1370`	`/// Splits the collection into two at the given key. Returns everything after the given key,`
`1371`		`- /// including the key.`
	`1371`	`+ /// including the key. If the key is not present, the split will occur at the nearest`
	`1372`	`+ /// greater key, or return an empty map if no such key exists.`
`1372`	`1373`	`///`
`1373`	`1374`	`/// # Examples`
`1374`	`1375`	`///`