public virtual ProgramNode NewReturnStatement(ProgramNode value) { return new StatementNode(); }
public virtual ProgramNode NewCondition(ProgramNode condition, ProgramNode truePart, ProgramNode falsePart) { return new ExpressionNode(); }
public virtual void Remove(ProgramNode node) { }
public virtual ProgramNode NewAssigment(ProgramNode variable, ProgramNode expression) { return new ExpressionNode(); }
public virtual void Add(ProgramNode node) { }