Merge commit 'a61d'

Conflicts:
	impl/Expression.hpp
	impl/Operator.hpp
	impl/Variable.hpp
	impl/main.cpp

1 files changed, 21 insertions, 9 deletions

diff --git a/impl/VariableAssignment.hpp b/impl/VariableAssignment.hpp
index 9d8137a..e0f7dc8 100644
--- a/impl/VariableAssignment.hpp
+++ b/impl/VariableAssignment.hpp
@@ -1,17 +1,29 @@
 #ifndef VARIABLE_ASSIGNMENT_HPP
 #define VARIABLE_ASSIGNMENT_HPP
 
-#include "Variable.hpp"
+#include "Expression.hpp"
 #include "IdMap.hpp"
 
-template<typename T>
-struct VariableAssignment : public IdMap<Variable<T>,T> {
-  VariableAssignment(unsigned int length)
-    : IdMap<Variable<T>,T>(length, -infinity<T>()) { }
-  VariableAssignment(unsigned int length, const T& initial)
-    : IdMap<Variable<T>,T>(length, initial) { }
-  VariableAssignment(const VariableAssignment& other)
-    : IdMap<Variable<T>,T>(other) { }
+template<typename Domain>
+struct VariableAssignment {
+  virtual ~VariableAssignment() { }
+  virtual const Domain& operator[](const Variable<Domain>&) const = 0;
+};
+
+template<typename Domain>
+struct StableVariableAssignment
+: public VariableAssignment<Domain>, public IdMap<Variable<Domain>, Domain> {
+  StableVariableAssignment(unsigned int length)
+    : IdMap<Variable<Domain>,Domain>(length, -infinity<Domain>()) { }
+  StableVariableAssignment(unsigned int length, const Domain& value)
+    : IdMap<Variable<Domain>,Domain>(length, value) { }
+
+  const Domain& operator[](const Variable<Domain>& var) const {
+    return IdMap<Variable<Domain>,Domain>::operator[](var);
+  }
+  Domain& operator[](const Variable<Domain>& var) {
+    return IdMap<Variable<Domain>,Domain>::operator[](var);
+  }
 };
 
 #endif