Add must_use to some CRDT functions

src/util/crdt/lww_map.rs

@@ -63,6 +63,7 @@ where
 	///
 	/// However extracting the mutator on its own and only sending that on the network is very
 	/// interesting as it is much smaller than the whole map.
+	#[must_use = "CRDT mutators are meant to be merged into a CRDT and not ignored."]
 	pub fn update_mutator(&self, k: K, new_v: V) -> Self {
 		let new_vals = match self.vals.binary_search_by(|(k2, _, _)| k2.cmp(&k)) {
 			Ok(i) => {

src/util/crdt/map.rs

@@ -33,6 +33,7 @@ where
 	/// This can be used to build a delta-mutator:
 	/// when merged with another map, the value will be added or CRDT-merged if a previous
 	/// value already exists.
+	#[must_use = "CRDT mutators are meant to be merged into a CRDT and not ignored."]
 	pub fn put_mutator(k: K, v: V) -> Self {
 		Self { vals: vec![(k, v)] }
 	}

src/util/crdt/mod.rs

@@ -7,7 +7,7 @@
 //! counter.  Alice does +1 on her copy, she reads 1.  Bob does +3 on his copy, he reads 3.  Now,
 //! it is easy to merge their counters, order does not count: we always get 4.
 //!
-//! Learn more about CRDT [on Wikipedia](https://en.wikipedia.org/wiki/Conflict-free_replicated_data_type)
+//! Learn more about CRDTs [on Wikipedia](https://en.wikipedia.org/wiki/Conflict-free_replicated_data_type)
 
 mod bool;
 #[allow(clippy::module_inception)]