fix: move multilambda template into class scope

Author: wdconinc

src/algorithms/calorimetry/CalorimeterIslandCluster.cc

@@ -34,10 +34,6 @@
 using namespace edm4eic;
 
 namespace eicrecon {
-template <typename... L> struct multilambda : L... {
-  using L::operator()...;
-  constexpr multilambda(L... lambda) : L(std::move(lambda))... {}
-};
 
 static double Phi_mpi_pi(double phi) { return std::remainder(phi, 2 * M_PI); }
 

src/algorithms/calorimetry/CalorimeterIslandCluster.h

@@ -70,6 +70,11 @@ class CalorimeterIslandCluster : public CalorimeterIslandClusterAlgorithm,
   dd4hep::IDDescriptor m_idSpec;
 
 private:
+  template <typename... L> struct multilambda : L... {
+    using L::operator()...;
+    constexpr multilambda(L... lambda) : L(std::move(lambda))... {}
+  };
+
   // grouping function with Breadth-First Search
   void bfs_group(const edm4eic::CalorimeterHitCollection& hits, std::set<std::size_t>& group,
                  std::size_t idx, std::vector<bool>& visits) const;

src/algorithms/calorimetry/ImagingTopoCluster.cc

@@ -37,10 +37,6 @@
 #include "algorithms/calorimetry/ImagingTopoClusterConfig.h"
 
 namespace eicrecon {
-template <typename... L> struct multilambda : L... {
-  using L::operator()...;
-  constexpr multilambda(L... lambda) : L(std::move(lambda))... {}
-};
 
 void ImagingTopoCluster::init() {
 

src/algorithms/calorimetry/ImagingTopoCluster.h

@@ -69,6 +69,11 @@ class ImagingTopoCluster : public ImagingTopoClusterAlgorithm,
   void process(const Input& input, const Output& output) const final;
 
 private:
+  template <typename... L> struct multilambda : L... {
+    using L::operator()...;
+    constexpr multilambda(L... lambda) : L(std::move(lambda))... {}
+  };
+
   // helper function to group hits
   bool is_neighbour(const edm4eic::CalorimeterHit& h1, const edm4eic::CalorimeterHit& h2) const;