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📄 fenxi.cpp

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		m_nErrNo=16;		//缺少 “ ( ”符号!"
		m_nErrAddr=m_nCur;
		return false;
	}

	m_nCur++;

	if (!y_XingCan())
		return false;

	while (m_cifa[m_nCur]->nType==30)	//;
	{
		m_nCur++;
		if (!y_XingCan()) 
			return false;
	}
	switch (m_cifa[m_nCur]->nType)
	{
	case 34:	//)
		break;
	default:
		m_nErrNo=17;   //缺少 “ ) ”符号!
		m_nErrAddr=m_nCur;
		return false;
	}
	m_nCur++;
	return true;
}


/*================================================================ 
* 函数名:    y_XingCan
* 功能描述:   分析形参 (protected)
* 返回值:    void
* 示例:	  Var m,n:Integer; t:Real
================================================================*/
bool CFenXi::y_XingCan()
{
	if (m_cifa[m_nCur]->nType==4)	//var
		m_nCur++;

	switch (m_cifa[m_nCur]->nType)
	{
	case 1:		//id
		break;

	default:
		m_nErrNo=18;		//"缺少形参标识符 !"
		m_nErrAddr=m_nCur;
		return false;
	}

	m_nCur++;

	while (m_cifa[m_nCur]->nType==32)	//, 用于分析多个形参的情况
	{
		m_nCur++;

		switch (m_cifa[m_nCur]->nType)
		{
		case 1:	//id
			break;

		default:
			m_nErrNo=18;	//"缺少形参标识符 !"
			m_nErrAddr=m_nCur;
			return false;
		}
		m_nCur++;
	}

	switch (m_cifa[m_nCur]->nType)
	{
	case 35:	//:
		break;
	default:
		m_nErrNo=19;	//缺少 “ : ”符号!
		m_nErrAddr=m_nCur;
		return false;
	}

	m_nCur++;

	switch (m_cifa[m_nCur]->nType)
	{
	case 14:	//booleger
	case 15:	//real
		break;
	default:
		m_nErrNo=12; //缺少保留字 integer 或 real!
		m_nErrAddr=m_nCur;
		return false;
	}
	m_nCur++;
	return true;
}



/*================================================================ 
* 函数名:    y_YuJuChuan
* 功能描述:   语句串,用分号隔开的多个语句 (protected)
* 返回值:    void
* 示例: 
				  x:=1;y:=2;z:=3;
				  Call ab(x,y,z);
				  z:=4+z+(1+2+6+x)*3*y*5+7;
				  If ~ 3<=x & y<>4 then z:=0;
				  y:=219;  z:=37;  x:=y*z
================================================================*/
bool CFenXi::y_YuJuChuan()
{
	if (!y_YuJu()) 
		return false;

	while (m_cifa[m_nCur]->nType==30)	//;
	{
		m_nCur++;
		if (!y_YuJu()) 
			return false;
	}
	return true;
}


/*================================================================ 
* 函数名:    y_YuJu
* 功能描述:   语句 (protected)
* 返回值:    void
================================================================*/
bool CFenXi::y_YuJu()
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 6:			//begin
		if (!y_FuHeYuJu())
			return false;
		break;

	case 1:			//id
		if (!y_FuZhiYuJu()) 
			return false;
		break;

	case 8:			//if
		if (!y_TiaoJianYuJu())
			return false;
		break;

	case 11:		//while
		if (!y_XunHuanYuJu()) 
			return false;
		break;

	case 13:		//call
		if (!y_GuoChengYuJu()) return false;
		break;

	default:
		m_nErrNo=9;   //缺少《语句》,应为 begin,ID,if,while,call
		m_nErrAddr=m_nCur;
		return false;
	}
	return true;
}



/*================================================================ 
* 函数名:    y_FuHeYuJu
* 功能描述:   复合语句 (protected)
* 返回值:    void
================================================================*/
bool CFenXi::y_FuHeYuJu() 
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 6:		//begin
		break;
	default:
		m_nErrNo=8;	//缺少保留字“ begin ”!
		m_nErrAddr=m_nCur;
		return false;
	}

	m_nCur++;

	if (!y_YuJuChuan()) //递归调用
		return false;

	switch (m_cifa[m_nCur]->nType)
	{
	case 7:		//end
		break;
	default:
		m_nErrNo=10;	//"缺少保留字“ end ”!
		m_nErrAddr=m_nCur;
		return false;
	}
	m_nCur++;

	return true;
}



/*================================================================ 
* 函数名:    y_FuZhiYuJu
* 功能描述:   赋值语句 (protected)
* 返回值:    void
* 示例:      y:=219;
================================================================*/
bool CFenXi::y_FuZhiYuJu()
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 1:		//id
		break;
	default:
		m_nErrNo=20; //缺少标识符!
		m_nErrAddr=m_nCur;
		return false;
	}

	m_nCur++;

	switch (m_cifa[m_nCur]->nType)
	{
	case 29:	//:=
		break;
	default:
		m_nErrNo=21;  //缺少赋值符号“ := ”!
		m_nErrAddr=m_nCur;
		return false;
	}


	m_nCur++;

	if (!y_BiaoDaShi()) 
		return false;

	return true;
}



/*================================================================ 
* 函数名:    y_TiaoJianYuJu
* 功能描述:   条件语句 (protected)
* 返回值:    void
* 示例:		If m>n then n:=m else t:=m;
================================================================*/
bool CFenXi::y_TiaoJianYuJu()
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 8:	//if
		break;
	default:
		m_nErrNo=22;  //缺少保留字“ if ”!
		m_nErrAddr=m_nCur;
		return false;
	}

	m_nCur++;

	if (!y_BuErBiaoDaShi())		//表达式
		return false;


	switch (m_cifa[m_nCur]->nType)
	{
	case 9:		//then
		break;
	default:
		m_nErrNo=23;  //缺少保留字“ then ”!
		m_nErrAddr=m_nCur;
		return false;
	}
	m_nCur++;

	if (!y_YuJu())		//语句
		return false;

	switch (m_cifa[m_nCur]->nType)
	{
	case 10:	//else
		break;
	default:
		return true;
	}
	m_nCur++;

	if (!y_YuJu())	//语句
		return false;

	return true;
}



/*================================================================ 
* 函数名:    y_XunHuanYuJu
* 功能描述:   循环语句	 (protected)
* 返回值:    void
* 示例:    
				While n<m do
						Begin
						  n:=n+1
						End
================================================================*/
bool CFenXi::y_XunHuanYuJu()
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 11:	//while
		break;
	default:
		m_nErrNo=24;
		m_nErrAddr=m_nCur;
		return false;
	}
	m_nCur++;

	if (!y_BuErBiaoDaShi())  //表达式
		return false;

	switch (m_cifa[m_nCur]->nType)
	{
	case 12:	//do
		break;

	default:
		m_nErrNo=25;   //缺少保留字“ do ”!
		m_nErrAddr=m_nCur;
		return false;
	}
	m_nCur++;

	if (!y_YuJu()) 
		return false;

	return true;
}



/*================================================================ 
* 函数名:    y_GuoChengYuJu
* 功能描述:   过程语句	 (protected)
* 返回值:    void
* 示例:	Call ab(x,y,z);
================================================================*/
bool CFenXi::y_GuoChengYuJu()
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 13:	//call
		break;

	default:
		m_nErrNo=26;	//缺少保留字“ call ”!
		m_nErrAddr=m_nCur;
		return false;
	}

	m_nCur++;

	switch (m_cifa[m_nCur]->nType)
	{
	case 1:		//id
		break;

	default:
		m_nErrNo=27;	//缺少被调过程名标识符!
		m_nErrAddr=m_nCur;
		return false;
	}

	m_nCur++;

	switch (m_cifa[m_nCur]->nType)
	{
	case 33:	//(
		break;
	default:
		return true;
	}
	if (!y_ShiCanBiao()) //表达式
		return false;

	return true;
}



/*================================================================ 
* 函数名:    y_ShiCanBiao
* 功能描述:   实参表 (protected)
* 返回值:    void
*示例:		Call ab(x,y,z);
================================================================*/
bool CFenXi::y_ShiCanBiao()
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 33:	//(
		break;
	default:
		m_nErrNo=16;	//缺少 “ ( ”符号!
		m_nErrAddr=m_nCur;
		return false;
	}

	m_nCur++;

	if (!y_BiaoDaShi())  //表达式
		return false;

	while (m_cifa[m_nCur]->nType==32)	//,
	{
		m_nCur++;
		if (!y_BiaoDaShi()) 
			return false;
	}

	switch (m_cifa[m_nCur]->nType)
	{
	case 34:	//)
		break;
	default:
		m_nErrNo=17;	//缺少 “ ) ”符号
		m_nErrAddr=m_nCur;
		return false;
	}
	m_nCur++;
	return true;
}



/*================================================================ 
* 函数名:    y_BiaoDaShi
* 功能描述:   表达式 (protected)
* 返回值:    void
* 示例:    z:=4+z+(1+2+6+x)*3*y*5+7;
================================================================*/
bool CFenXi::y_BiaoDaShi()
{
	if (!y_Xiang())
		return false;

	while (m_cifa[m_nCur]->nType==16)	//+
	{
		m_nCur++;
		if (!y_Xiang()) 
			return false;
	}

	return true;
}



/*================================================================ 
* 函数名:    y_Xiang
* 功能描述:   项 (protected)
* 返回值:    void
================================================================*/
bool CFenXi::y_Xiang()
{
	if (!y_YinZi()) 
		return false;

	while (m_cifa[m_nCur]->nType==18)//*
	{
		m_nCur++;
		if (!y_YinZi())
			return false;
	}

	return true;
}



/*================================================================ 
* 函数名:    y_YinZi
* 功能描述:   因子 (protected)
* 返回值:    void
================================================================*/
bool CFenXi::y_YinZi()
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 1:			//id
		m_nCur++;
		break;

	case 2:			//num
		m_nCur++;
		break;

	case 33:		//(
		m_nCur++;

		if (!y_BiaoDaShi())  //递归调用
			return false;

		switch (m_cifa[m_nCur]->nType)
		{
		case 34:	//)
			break;
		default:
			m_nErrNo=17;  //缺少 “ ) ”符号!
			m_nErrAddr=m_nCur;
			return false;
		}
		m_nCur++;

		break;

		default:
			m_nErrNo=28; //缺少《因子》,应为 (,ID,NUMBER"
			m_nErrAddr=m_nCur;
			return false;
	}
	return true;
}



/*================================================================ 
* 函数名:    y_BuErBiaoDaShi
* 功能描述:   布尔表达式 (protected)
* 返回值:    void
================================================================*/
bool CFenXi::y_BuErBiaoDaShi()
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 20:	//~
		m_nCur++;
		if (!y_BuErBiaoDaShi())
			return false;
		break;

	case 33:	//(
	case 1:		//id
	case 2:		//num
		if (!y_GuanXiBiaoDaShi()) 
			return false;

		while (m_cifa[m_nCur]->nType==21 || m_cifa[m_nCur]->nType==22) // & |
		{
			m_nCur++;
			if (!y_BuErBiaoDaShi())
				return false;
		}
		break;

	default:
		m_nErrNo=29;		//"缺少《布尔表达式》,应为 ~,(,ID,NUMBER"
		m_nErrAddr=m_nCur;
		return false;
	}
	return true;
}



/*================================================================ 
* 函数名:    y_GuanXiBiaoDaShi
* 功能描述:   关系表达式 (protected)
* 返回值:    void
================================================================*/
bool CFenXi::y_GuanXiBiaoDaShi()
{
	if (!y_BiaoDaShi())  //表达式
		return false;

	if (!y_GuanXi())	//关系
		return false;

	if (!y_BiaoDaShi())	//表达式
		return false;

	return true;
}



/*================================================================ 
* 函数名:    y_GuanXi
* 功能描述:   关系   (protected)
* 返回值:    void
================================================================*/
bool CFenXi::y_GuanXi()
{
	switch (m_cifa[m_nCur]->nType)
	{
	case 23:	//<
	case 24:	//<=
	case 25:	//>
	case 26:	//>=
	case 27:	//=
	case 28:	//<>
		break;

	default:
		m_nErrNo=30;	//缺少关系(<,<=,>,>=,=,<>)!
		m_nErrAddr=m_nCur;
		return false;
	}
	m_nCur++;
	return true;
}


/*================================================================ 
* 函数名:    init
* 功能描述:   用于初始化关键字表和错误信息表   (protected)
* 返回值:    void
================================================================*/
void CFenXi::init()
{
 	strcpy(m_szKW[0],"");
	strcpy(m_szKW[1],"");//标识符
	strcpy(m_szKW[2],"");//正整数
	strcpy(m_szKW[3],"program");
	strcpy(m_szKW[4],"var");
	strcpy(m_szKW[5],"procedure");
	strcpy(m_szKW[6],"begin");
	strcpy(m_szKW[7],"end");
	strcpy(m_szKW[8],"if");
	strcpy(m_szKW[9],"then");
	strcpy(m_szKW[10],"else");
	strcpy(m_szKW[11],"while");
	strcpy(m_szKW[12],"do");
	strcpy(m_szKW[13],"call");
	strcpy(m_szKW[14],"integer");
	strcpy(m_szKW[15],"real");
	strcpy(m_szKW[16],"+");
	strcpy(m_szKW[17],"-");
	strcpy(m_szKW[18],"*");
	strcpy(m_szKW[19],"/");
	strcpy(m_szKW[20],"~");
	strcpy(m_szKW[21],"&");
	strcpy(m_szKW[22],"|");
	strcpy(m_szKW[23],"<");
	strcpy(m_szKW[24],"<=");
	strcpy(m_szKW[25],">");
	strcpy(m_szKW[26],">=");
	strcpy(m_szKW[27],"=");
	strcpy(m_szKW[28],"<>");
	strcpy(m_szKW[29],":=");
	strcpy(m_szKW[30],";");
	strcpy(m_szKW[31],".");
	strcpy(m_szKW[32],",");
	strcpy(m_szKW[33],"(");
	strcpy(m_szKW[34],")");
	strcpy(m_szKW[35],":");
	strcpy(m_szKW[36],"/*");
	strcpy(m_szKW[37],"*/");
	strcpy(m_szKW[38],"");
	strcpy(m_szKW[39],"");
	strcpy(m_szKW[40],"");
	strcpy(m_szKW[41],"");
	strcpy(m_szKW[42],"");
	strcpy(m_szKW[43],"");
	strcpy(m_szKW[44],"");
	strcpy(m_szKW[45],"");
	strcpy(m_szKW[46],"");
	strcpy(m_szKW[47],"");
	strcpy(m_szKW[48],"");
	strcpy(m_szKW[49],"");
	strcpy(m_szErrMsg[0],"正确!");
	strcpy(m_szErrMsg[1],"数字位数过长!");
	strcpy(m_szErrMsg[2],"非法字符!");
	strcpy(m_szErrMsg[3],"缺少关键字“ program ”!");
	strcpy(m_szErrMsg[4],"program 后缺少标识符!");
	strcpy(m_szErrMsg[5],"缺少“ ; ”符号!");
	strcpy(m_szErrMsg[6],"缺少程序结束符“ . ”符号!");
	strcpy(m_szErrMsg[7],"缺少《程序体》,应为 begin,integer,real,procedure");
	strcpy(m_szErrMsg[8],"缺少保留字“ begin ”!");
	strcpy(m_szErrMsg[9],"缺少《语句》,应为 begin,ID,if,while,call");
	strcpy(m_szErrMsg[10],"缺少保留字“ end ”!");
	strcpy(m_szErrMsg[11],"缺少《声明》,应为 integer,real,procedure");
	strcpy(m_szErrMsg[12],"缺少保留字 integer 或 real!");
	strcpy(m_szErrMsg[13],"procedure 后缺少标识符!");
	strcpy(m_szErrMsg[14],"变量声明后缺少标识符!");
	strcpy(m_szErrMsg[15],"缺少保留字“ procedure ”!");
	strcpy(m_szErrMsg[16],"缺少 “ ( ”符号!");
	strcpy(m_szErrMsg[17],"缺少 “ ) ”符号!");
	strcpy(m_szErrMsg[18],"缺少形参标识符 !");
	strcpy(m_szErrMsg[19],"缺少 “ : ”符号!");
	strcpy(m_szErrMsg[20],"缺少标识符!");
	strcpy(m_szErrMsg[21],"缺少赋值符号“ := ”!");
	strcpy(m_szErrMsg[22],"缺少保留字“ if ”!");
	strcpy(m_szErrMsg[23],"缺少保留字“ then ”!");
	strcpy(m_szErrMsg[24],"缺少保留字“ while ”!");
	strcpy(m_szErrMsg[25],"缺少保留字“ do ”!");
	strcpy(m_szErrMsg[26],"缺少保留字“ call ”!");
	strcpy(m_szErrMsg[27],"缺少被调过程名标识符!");
	strcpy(m_szErrMsg[28],"缺少《因子》,应为 (,ID,NUMBER");
	strcpy(m_szErrMsg[29],"缺少《布尔表达式》,应为 ~,(,ID,NUMBER");
	strcpy(m_szErrMsg[30],"缺少《关系》!");
	strcpy(m_szErrMsg[31],"变量名不能和过程名相同!");
	strcpy(m_szErrMsg[32],"标识符重复声明!");
	strcpy(m_szErrMsg[33],"未声明标识符!");
	strcpy(m_szErrMsg[34],"不能直接引用过程名!");
	strcpy(m_szErrMsg[35],"不能从real转换为integer类型!");
	strcpy(m_szErrMsg[36],"不能用常数作实参!");
	strcpy(m_szErrMsg[37],"变参应为变量!");
	strcpy(m_szErrMsg[38],"实参个数不足!");
	strcpy(m_szErrMsg[39],"只有integer和integer才能比较!");
	strcpy(m_szErrMsg[40],"不能这样调用过程!");
	strcpy(m_szErrMsg[41],"");
	strcpy(m_szErrMsg[42],"");
	strcpy(m_szErrMsg[43],"");
	strcpy(m_szErrMsg[96],"源程序结束符 end. 后还有多余内容!");
	strcpy(m_szErrMsg[97],"语法错误太多,终止语法分析!");
	strcpy(m_szErrMsg[98],"源程序不正常结束!");
	strcpy(m_szErrMsg[99],"内存不足!词法分析终止!");
}


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