diff --git a/src/algorithm/nest_cfgs.rs b/src/algorithm/nest_cfgs.rs
index ab53724d0..2739160c9 100644
--- a/src/algorithm/nest_cfgs.rs
+++ b/src/algorithm/nest_cfgs.rs
@@ -104,7 +104,7 @@ fn all_edges<'a, T: Copy + Clone + PartialEq + Eq + Hash + 'a>(
         vec![]
     };
     cfg.successors(n)
-        .chain(extra.into_iter())
+        .chain(extra)
         .map(EdgeDest::Forward)
         .chain(cfg.predecessors(n).map(EdgeDest::Backward))
         .unique()
@@ -389,7 +389,7 @@ impl<T: Copy + Clone + PartialEq + Eq + Hash> EdgeClassifier<T> {
         let highest_target = be_up
             .into_iter()
             .map(|(dfs, _)| dfs)
-            .chain(min_dfs_target[0].into_iter());
+            .chain(min_dfs_target[0]);
         (highest_target.min().unwrap_or(usize::MAX), bs)
     }
 }
diff --git a/src/builder/build_traits.rs b/src/builder/build_traits.rs
index 88a002264..e2077e477 100644
--- a/src/builder/build_traits.rs
+++ b/src/builder/build_traits.rs
@@ -378,7 +378,7 @@ pub trait Dataflow: Container {
             just_inputs.into_iter().unzip();
         let (rest_types, rest_input_wires): (Vec<Type>, Vec<Wire>) =
             inputs_outputs.into_iter().unzip();
-        input_wires.extend(rest_input_wires.into_iter());
+        input_wires.extend(rest_input_wires);
 
         let tail_loop = ops::TailLoop {
             just_inputs: input_types.into(),
diff --git a/src/builder/cfg.rs b/src/builder/cfg.rs
index 199cbc3d8..914f53c50 100644
--- a/src/builder/cfg.rs
+++ b/src/builder/cfg.rs
@@ -228,7 +228,7 @@ impl<B: AsMut<Hugr> + AsRef<Hugr>> BlockBuilder<B> {
         branch_wire: Wire,
         outputs: impl IntoIterator<Item = Wire>,
     ) -> Result<(), BuildError> {
-        Dataflow::set_outputs(self, [branch_wire].into_iter().chain(outputs.into_iter()))
+        Dataflow::set_outputs(self, [branch_wire].into_iter().chain(outputs))
     }
     fn create(
         base: B,
diff --git a/src/builder/tail_loop.rs b/src/builder/tail_loop.rs
index ba1d15764..ed463c6b6 100644
--- a/src/builder/tail_loop.rs
+++ b/src/builder/tail_loop.rs
@@ -32,7 +32,7 @@ impl<B: AsMut<Hugr> + AsRef<Hugr>> TailLoopBuilder<B> {
         out_variant: Wire,
         rest: impl IntoIterator<Item = Wire>,
     ) -> Result<(), BuildError> {
-        Dataflow::set_outputs(self, [out_variant].into_iter().chain(rest.into_iter()))
+        Dataflow::set_outputs(self, [out_variant].into_iter().chain(rest))
     }
 
     /// Get a reference to the [`ops::TailLoop`]
diff --git a/src/ops/controlflow.rs b/src/ops/controlflow.rs
index ee96b2cc2..395516943 100644
--- a/src/ops/controlflow.rs
+++ b/src/ops/controlflow.rs
@@ -71,10 +71,9 @@ impl DataflowOpTrait for Conditional {
 
     fn signature(&self) -> FunctionType {
         let mut inputs = self.other_inputs.clone();
-        inputs.to_mut().insert(
-            0,
-            Type::new_predicate(self.predicate_inputs.clone().into_iter()),
-        );
+        inputs
+            .to_mut()
+            .insert(0, Type::new_predicate(self.predicate_inputs.clone()));
         FunctionType::new(inputs, self.outputs.clone())
     }
 }