message: Use implicit iterator
diff: @@ -86,7 +86,7 @@ impl LookupInfo {
  /// Check what kind of lookups, if any, are used by this circuit.
  pub fn lookup_used(&self) -> Option<LookupsUsed> {
  let mut lookups_used = None;
  - for lookup_pattern in self.kinds.iter() {
  + for lookup_pattern in &self.kinds {
  if lookup_pattern.max_joint_size() > 1 {
  return Some(LookupsUsed::Joint);
  } else {
  