#ifndef VARIABLE_ASSIGNMENT_HPP
#define VARIABLE_ASSIGNMENT_HPP

#include "Expression.hpp"
#include "IdMap.hpp"

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