Added to_string for ModelType

Former-commit-id: e1cf746727 [formerly 912ca0f4f3]
Former-commit-id: 9ebb580890

src/storage/jani/ModelType.cpp

@@ -4,48 +4,38 @@ namespace storm {
     namespace jani {
         
         std::ostream& operator<<(std::ostream& stream, ModelType const& type) {
+            return stream << to_string(type);
+        }
+        
+        std::string to_string(ModelType const& type) {
             switch (type) {
                 case ModelType::UNDEFINED:
-                    stream << "undefined";
-                    break;
+                    return "undefined";
                 case ModelType::LTS:
-                    stream << "lts";
-                    break;
+                    return "lts";
                 case ModelType::DTMC:
-                    stream << "dtmc";
-                    break;
+                    return "dtmc";
                 case ModelType::CTMC:
-                    stream << "ctmc";
-                    break;
+                    return "ctmc";
                 case ModelType::MDP:
-                    stream << "mdp";
-                    break;
+                    return "mdp";
                 case ModelType::CTMDP:
-                    stream << "ctmdp";
-                    break;
+                    return "ctmdp";
                 case ModelType::MA:
-                    stream << "ma";
-                    break;
+                    return "ma";
                 case ModelType::TA:
-                    stream << "ta";
-                    break;
+                    return "ta";
                 case ModelType::PTA:
-                    stream << "pta";
-                    break;
+                    return "pta";
                 case ModelType::STA:
-                    stream << "sta";
-                    break;
+                    return "sta";
                 case ModelType::HA:
-                    stream << "ha";
-                    break;
+                    return "ha";
                 case ModelType::PHA:
-                    stream << "pha";
-                    break;
+                    return "pha";
                 case ModelType::SHA:
-                    stream << "sha";
-                    break;
+                    return "sha";
             }
-            return stream;
         }
 
         ModelType getModelType(std::string const& input) {

src/storage/jani/ModelType.h

@@ -10,6 +10,7 @@ namespace storm {
                             HA = 10, PHA = 11, SHA = 12};
 
         ModelType getModelType(std::string const& input);
+        std::string to_string(ModelType const& type);
         std::ostream& operator<<(std::ostream& stream, ModelType const& type);
         
     }