express.cpp

这是c++编程方面的名著的例子代码

  #include "express.h"
  #include <String.h>


//==================================================================
expression_component::expression_component(void)
{
	 IsOperand = 0;
	 IsOperator = 0;
	 IsFunction = 0;
}

expression_component::expression_component(const expression_component &X)
{
	 Exponent = X.Exponent;
	 Value = X.Value;
	 Sign = X.Sign;
	 Variable = X.Variable;
	 Priority = X.Priority;
	 Operator = X.Operator;
	 IsOperator = X.IsOperator;
	 IsOperand = X.IsOperand;
	 IsFunction = X.IsFunction;
	 strcpy(Function,X.Function);

}
int expression_component::isOperator(void)
{
	  return(IsOperator);
}

void expression_component::isOperator(int Bool)
{

	  IsOperator = Bool;
}

int expression_component::isOperand(void)
{
	 return(IsOperand);

}

void expression_component::isOperand(int X)
{
     IsOperand = X;
}

int expression_component::isFunction(void)
{
     return(IsFunction);
}

void expression_component::isFunction(int X)
{
     IsFunction = X;
}

expression_component &expression_component::operator=(const expression_component &X)
{
	 Exponent = X.Exponent;
	 Value = X.Value;
	 Sign = X.Sign;
	 Variable = X.Variable;
	 Priority = X.Priority;
	 Operator = X.Operator;
	 IsOperator = X.IsOperator;
	 IsOperand = X.IsOperand;
	 IsFunction = X.IsFunction;
	 strcpy(Function,X.Function);
	 return(*this);

}

int expression_component::operator>(const expression_component &X) const
{
      if(X.IsOperand){
	 if(Value > X.Value){
	    return(1);
	 }
	 else{
	       return(0);
	 }
      }
      else
	  if(Priority > X.Priority){
	     return(1);
	  }
	  else{
		return(0);
	  }
}
int expression_component::operator()(expression_component &X,expression_component &Y)
{
	if(X.IsOperand){
	 if(X.Variable < Y.Variable){

	    return(1);
	 }
	 else{
	       return(0);
	 }
      }
      else
	  if((X.Priority < Y.Priority) &&
	     (X.Operator < Y.Operator)){
	     return(1);
	  }
	  else{
		return(0);
	  }
}

int expression_component::operator<(const expression_component &X) const
{
       if(X.IsOperand){
	 if(Variable < X.Variable){

	    return(1);
	 }
	 else{
	       return(0);
	 }
      }
      else
	  if((Priority < X.Priority) &&
	     (Operator < X.Operator)){
	     return(1);
	  }

	  else{
		return(0);
	  }
}

int expression_component::operator==(const expression_component &X) const
{
      if(X.IsOperand){
	 if(Variable == X.Variable){
	    return(1);
	 }
	 else{
	       return(0);
	 }
      }
      else
	  if((Priority == X.Priority) &&
	     (Operator == X.Operator)){
	     return(1);
	  }
	  else{
		return(0);
	  }
}

int expression_component::operator>=(expression_component &X)
{

      if(X.IsOperand){
	 if(Value >= X.Value){
	    return(1);
	 }
	 else{
	       return(0);
	 }
      }
      else
	  if(Priority >= X.Priority){
	     return(1);
	  }
	  else{
		return(0);
	  }

}

int expression_component::operator<=(expression_component &X)
{
      if(X.IsOperand){
	 if(Value <= X.Value){
	    return(1);
	 }
	 else{
	       return(0);
	 }
      }
      else
	  if(Priority <= X.Priority){
	     return(1);
	  }
	  else{
		return(0);
	  }


}


int expression_component::operator!=(expression_component &X)
{

     if(X.IsOperand){
	 if(Value != X.Value){
	    return(1);
	 }
	 else{
	       return(0);
	 }
      }
      else
	  if(Priority != X.Priority){
	     return(1);
	  }
	  else{
		return(0);
	  }


}

operand expression_component::operand_type(void)
{
    operand Temp;
    Temp.exponent(Exponent);
    Temp.value(Value);
    Temp.sign(Sign);
    Temp.variable(Variable);
    return(Temp);
}



operator_type expression_component::opType(void)
{
     operator_type Temp;
     Temp.priority(Priority);
     Temp.op(Operator);
     Temp.function(Function);
     return(Temp);

}




ostream &operator<<(ostream &Out,expression_component &X)
{

     Out << X.IsOperand << " " << X.IsOperator << endl;
     Out << "Value " << X.Value  << endl;
     Out << "Function " << X.Function << endl;
     Out << "Variable " << X.Variable << endl;
     Out << "Operator " << X.Operator << endl;
     return(Out);

}