1 files changed, 37 insertions, 0 deletions
diff --git a/ecs/src/component.rs b/ecs/src/component.rs
index 6fb1230..5a8cd0b 100644
--- a/ecs/src/component.rs
+++ b/ecs/src/component.rs
@@ -2,6 +2,8 @@ use std::any::{type_name, Any};
 use std::fmt::Debug;
 use std::ops::{Deref, DerefMut};
 
+use ecs_macros::Component;
+use hashbrown::HashSet;
 use seq_macro::seq;
 
 use crate::lock::{
@@ -311,3 +313,38 @@ impl Default for PartsBuilder
         Self { name: "(unspecified)" }
     }
 }
+
+/// Pending component removals for a entity.
+#[derive(Debug, Clone, Component)]
+pub struct Removals
+{
+    component_ids: HashSet<Uid>,
+}
+
+impl Removals
+{
+    pub fn contains<ComponentT: Component>(&self) -> bool
+    {
+        self.contains_id(ComponentT::id())
+    }
+
+    pub fn contains_id(&self, component_id: Uid) -> bool
+    {
+        self.component_ids.contains(&component_id)
+    }
+
+    pub(crate) fn add_ids(&mut self, ids: impl IntoIterator<Item = Uid>)
+    {
+        self.component_ids.extend(ids)
+    }
+}
+
+impl FromIterator<Uid> for Removals
+{
+    fn from_iter<T: IntoIterator<Item = Uid>>(iter: T) -> Self
+    {
+        Self {
+            component_ids: iter.into_iter().collect(),
+        }
+    }
+}