Dataset length

crates/pile-value/src/source/mod.rs

@@ -8,6 +8,9 @@ pub mod misc;
 
 /// A read-only set of [Item]s.
 pub trait DataSource {
+	/// Get the number of items in this source
+	fn len(&self) -> usize;
+
 	/// Get an item from this datasource
 	fn get(
 		&self,