Added convenience operator overloads for more readable code :)

Former-commit-id: 082f19bede [formerly 94b4f6284f]
Former-commit-id: c95b0dc93f

src/storage/expressions/Expression.cpp

@@ -185,11 +185,26 @@ namespace storm {
             return Expression(std::shared_ptr<BaseExpression>(new BinaryNumericalFunctionExpression(first.getManager(), first.getType().plusMinusTimes(second.getType()), first.getBaseExpressionPointer(), second.getBaseExpressionPointer(), BinaryNumericalFunctionExpression::OperatorType::Plus)));
         }
         
+        Expression operator+(Expression const& first, int64_t second) {
+            return first + Expression(std::shared_ptr<BaseExpression>(new IntegerLiteralExpression(first.getBaseExpression().getManager(), second)));
+        }
+        
+        Expression operator+(int64_t first, Expression const& second) {
+            return second + first;
+        }
+        
         Expression operator-(Expression const& first, Expression const& second) {
             assertSameManager(first.getBaseExpression(), second.getBaseExpression());
             return Expression(std::shared_ptr<BaseExpression>(new BinaryNumericalFunctionExpression(first.getBaseExpression().getManager(), first.getType().plusMinusTimes(second.getType()), first.getBaseExpressionPointer(), second.getBaseExpressionPointer(), BinaryNumericalFunctionExpression::OperatorType::Minus)));
         }
         
+        Expression operator-(Expression const& first, int64_t second) {
+            return first - Expression(std::shared_ptr<BaseExpression>(new IntegerLiteralExpression(first.getBaseExpression().getManager(), second)));
+        }
+        
+        Expression operator-(int64_t first, Expression const& second) {
+            return Expression(std::shared_ptr<BaseExpression>(new IntegerLiteralExpression(second.getBaseExpression().getManager(), first))) - second;        }
+        
         Expression operator-(Expression const& first) {
             return Expression(std::shared_ptr<BaseExpression>(new UnaryNumericalFunctionExpression(first.getBaseExpression().getManager(), first.getType().minus(), first.getBaseExpressionPointer(), UnaryNumericalFunctionExpression::OperatorType::Minus)));
         }

src/storage/expressions/Expression.h

@@ -23,7 +23,11 @@ namespace storm {
             template<typename MapType> friend class SubstitutionVisitor;
             
             friend Expression operator+(Expression const& first, Expression const& second);
+            friend Expression operator+(Expression const& first, int64_t second);
+            friend Expression operator+(int64_t first, Expression const& second);
             friend Expression operator-(Expression const& first, Expression const& second);
+            friend Expression operator-(Expression const& first, int64_t second);
+            friend Expression operator-(int64_t first, Expression const& second);
             friend Expression operator-(Expression const& first);
             friend Expression operator*(Expression const& first, Expression const& second);
             friend Expression operator/(Expression const& first, Expression const& second);
@@ -328,7 +332,11 @@ namespace storm {
         
         // Provide operator overloads to conveniently construct new expressions from other expressions.
         Expression operator+(Expression const& first, Expression const& second);
+        Expression operator+(Expression const& first, int64_t second);
+        Expression operator+(int64_t first, Expression const& second);
         Expression operator-(Expression const& first, Expression const& second);
+        Expression operator-(Expression const& first, int64_t second);
+        Expression operator-(int64_t first, Expression const& second);
         Expression operator-(Expression const& first);
         Expression operator*(Expression const& first, Expression const& second);
         Expression operator/(Expression const& first, Expression const& second);