DPL: reduce template instanciation (#6290)

Author: ktf

Framework/Core/include/Framework/DispatchPolicy.h

@@ -49,7 +49,9 @@ struct DispatchPolicy {
   /// the action to be used for matched devices
   DispatchOp action = DispatchOp::AfterComputation;
   /// matcher on specific output to trigger sending
-  TriggerMatcher triggerMatcher = [](Output const&) { return true; };
+  TriggerMatcher triggerMatcher = defaultDispatchPolicy();
+
+  static TriggerMatcher defaultDispatchPolicy();
 
   /// Helper to create the default configuration.
   static std::vector<DispatchPolicy> createDefaultPolicies();

Framework/Core/src/DispatchPolicy.cxx

@@ -25,6 +25,11 @@ std::vector<DispatchPolicy> DispatchPolicy::createDefaultPolicies()
   return {DispatchPolicy{"dispatch-all-after-computation", [](DeviceSpec const&) { return true; }, DispatchPolicy::DispatchOp::AfterComputation}};
 }
 
+DispatchPolicy::TriggerMatcher DispatchPolicy::defaultDispatchPolicy()
+{
+  return DispatchPolicy::TriggerMatcher{[](Output const&) -> bool { return true; }};
+}
+
 std::ostream& operator<<(std::ostream& oss, DispatchPolicy::DispatchOp const& val)
 {
   switch (val) {