1 files changed, 16 insertions, 12 deletions
diff --git a/server/protocol/src/helpers.rs b/server/protocol/src/helpers.rs
index 90dfd6ff..679e6301 100644
--- a/server/protocol/src/helpers.rs
+++ b/server/protocol/src/helpers.rs
@@ -74,19 +74,23 @@ impl Recipe {
             _ => false,
         }
     }
-    pub fn inputs(&self) -> Vec<ItemIndex> {
-        match self {
-            Recipe::Passive { input, .. } => vec![*input],
-            Recipe::Active { input, .. } => vec![*input],
-            Recipe::Instant { inputs, .. } => inputs.iter().flat_map(|e| e.to_owned()).collect(),
-        }
+    pub fn inputs(&self) -> impl Iterator<Item = ItemIndex> {
+        let (a, b) = match self {
+            Recipe::Passive { input, .. } | Recipe::Active { input, .. } => (Some(input), None),
+            Recipe::Instant { inputs, .. } => (inputs[0].as_ref(), inputs[1].as_ref()),
+        };
+
+        a.into_iter().chain(b).copied()
     }
-    pub fn outputs(&self) -> Vec<ItemIndex> {
-        match self {
-            Recipe::Passive { output, .. } => output.iter().copied().collect(),
-            Recipe::Active { outputs, .. } => outputs.iter().flat_map(|e| e.to_owned()).collect(),
-            Recipe::Instant { outputs, .. } => outputs.iter().flat_map(|e| e.to_owned()).collect(),
-        }
+    pub fn outputs(&self) -> impl Iterator<Item = ItemIndex> {
+        let (a, b) = match self {
+            Recipe::Passive { output, .. } => (output, &None),
+            Recipe::Active { outputs, .. } | Recipe::Instant { outputs, .. } => {
+                (&outputs[0], &outputs[1])
+            }
+        };
+
+        a.iter().chain(b.iter()).copied()
     }
     pub fn supports_tile(&self, tile: Option<TileIndex>) -> bool {
         if let Some(tile_constraint) = self.tile() {