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我有用于 c/c++ 的词法分析器的代码，该代码适用于表达式，如何将其用于 ac/c++ 源文件。我试过像下面的代码..它产生不正确的令牌集..

代码：

    #include<iostream.h>
#include<conio.h>
#include<string.h>
#include<ctype.h>
#include<stdio.h>
#include<fstream.h>
#include<stdlib.h>
class Lex_Ana
{
public :
    int i,j,k,ti,oprfl,delfl,keyfl,Litfl,cLitfl,ptfl,tfl,mxIdeni,Liti,mxIdenj,mxOpri,mxOprj,mxDeli,Erri;
    int uqIdi,uqOpi,uqDei,defOpi,defKeyi,cLiti;
    char mStr[50],mxIden[20][20],mxOpr[20][20],mxDel[20],tmpStr[50];
    char defOprStr[20][20],defOpr[15],defDel[15],defKey[20][20];
    char uqOpr[20][20],uqIden[20][20],uqIdfl[20],uqOpfl[20],uqDefl[20],uqDel[20];
    char Opr[20][20],invalTok[20][20],Con[20][20],Iden[20][20],
         Key[20][20],inTok[20],Lit[20][20],Err[20][20],cLit[20][20];
    int Opri,invToki,Coni,Ideni,Keyi,Deli,inToki;

    Lex_Ana(char *str)
    {
        strcpy(mStr,str);

        //Defined Keywords
        defKeyi=13;
        strcpy(defKey[0],"int");
        strcpy(defKey[1],"float");
        strcpy(defKey[2],"double");
        strcpy(defKey[3],"for");
        strcpy(defKey[4],"if");
        strcpy(defKey[5],"else");
        strcpy(defKey[6],"while");
        strcpy(defKey[7],"do");
        strcpy(defKey[8],"return");
        strcpy(defKey[9],"char");
        strcpy(defKey[10],"break");
        strcpy(defKey[11],"goto");
        strcpy(defKey[12],"void");

        //Defined Operators
        defOpi=18;
        strcpy(defOprStr[0],"+");
        strcpy(defOprStr[1],"-");
        strcpy(defOprStr[2],"*");
        strcpy(defOprStr[3],"/");
        strcpy(defOprStr[4],"%");
        strcpy(defOprStr[5],"=");
        strcpy(defOprStr[6],"<");
        strcpy(defOprStr[7],">");
        strcpy(defOprStr[8],"<=");
        strcpy(defOprStr[9],">=");
        strcpy(defOprStr[10],"==");
        strcpy(defOprStr[11],"=+");
        strcpy(defOprStr[12],"=-");
        strcpy(defOprStr[13],"=*");
        strcpy(defOprStr[14],"=/");
        strcpy(defOprStr[15],"=%");
        strcpy(defOprStr[16],"++");
        strcpy(defOprStr[17],"--");
        strcpy(defOpr,"+-/*%=<>");
        strcpy(defDel,";,:{}[]()");
    }

    int IsMxIden(char ch)
    {
        return((IsIden(ch)||IsFloat(ch))?1:0);
    }

    int IsIden(char ch)
    {
        return((isalpha(ch)||ch=='_')?1:0);
    }

    int IsFloat(char ch)
    {
        return((isdigit(ch)||ch=='.')?1:0);
    }

    int IsOpr(char ch)
    {
        oprfl=0;
        for(ti=0;ti<strlen(defOpr)&&!oprfl;ti++)
        {
        if(ch==defOpr[ti])
        {
            oprfl=1;
        }
        }
        return oprfl;
    }

    int IsDel(char ch)
    {
        delfl=0;
        for(ti=0;ti<strlen(defDel)&&!delfl;ti++)
        {
        if(ch==defDel[ti])
        {
            delfl=1;
        }
        }
        return delfl;
    }

    int IsKey(char *str)
    {
        keyfl=0;
        for(ti=0;ti<defKeyi&&!keyfl;ti++)
        {
        if(!strcmp(defKey[ti],str))
        {
            keyfl=1;
        }
        }
        return keyfl;
    }


    void Find_Lex()
    {
        i=0;
        cLiti=0;
        Liti=0;
        Erri=0;
        mxIdeni=0;
        mxIdenj=0;
        mxOpri=0;
        mxOprj=0;
        mxDeli=0;
        inToki=0;
        while(mStr[i]!='\0')
        {
        if(IsMxIden(mStr[i]))
        {
            while(IsMxIden(mStr[i]))
            {
            mxIden[mxIdeni][mxIdenj++]=mStr[i++];
            if(!IsMxIden(mStr[i]))
            {
                mxIden[mxIdeni++][mxIdenj]='\0';
                mxIdenj=0;
            }
            }
        }
        else if(mStr[i]=='"')
        {
            Litfl=1;
            k=0;
            tmpStr[k++]=mStr[i];
            for(j=i+1;j<strlen(mStr)&&Litfl;j++)
            {
                tmpStr[k++]=mStr[j];
                if(mStr[j]=='"')
                {
                    tmpStr[k]='\0';
                    strcpy(Lit[Liti++],tmpStr);
                    Litfl=0;
                    i=j+1;
                }
            }
            if(Litfl)
            {
                strcpy(Err[Erri++],"Invalid Use of \"");
                i++;
            }
        }
        else if(mStr[i]=='\'')
        {
            cLitfl=0;
            k=0;
            tmpStr[k++]=mStr[i];
            for(j=i+1;j<strlen(mStr)&&!cLitfl;j++)
            {
                tmpStr[k++]=mStr[j];
                if(mStr[j]=='\'')
                {
                    tmpStr[k]='\0';
                    if(strlen(tmpStr)!=3)
                    {
                        strcpy(Err[Erri++],"Invalid Use of \'");
                        cLitfl=1;
                        i++;
                    }
                    else
                    {
                        strcpy(cLit[cLiti++],tmpStr);
                        cLitfl=1;
                        i=j+1;
                    }
                }
            }
            if(!cLitfl)
            {
                strcpy(Err[Erri++],"Invalid Use of \'");
                cLitfl=1;
                i++;
            }
        }
        else if(IsOpr(mStr[i]))
        {
            while(IsOpr(mStr[i]))
            {
            mxOpr[mxOpri][mxOprj++]=mStr[i++];
            if(!IsOpr(mStr[i]))
            {
                mxOpr[mxOpri++][mxOprj]='\0';
                mxOprj=0;
            }
            }
        }
        else if(IsDel(mStr[i]))
        {
            while(IsDel(mStr[i]))
            {
            mxDel[mxDeli++]=mStr[i++];
            }
            mxDel[mxDeli]='\0';
        }
        else if(mStr[i]!=' ')
        {
            inTok[inToki++]=mStr[i++];
            inTok[inToki]='\0';
        }
        else
        {
            i++;
        }
        }
    }

    void Rem_Dup()
    {
        uqIdi=0;
        uqDei=0;
        uqOpi=0;
        for(i=0;i<20;i++)
        {
        uqOpfl[i]=0;
        uqIdfl[i]=0;
        uqDefl[i]=0;
        }
        for(i=1;i<mxIdeni+1;i++)
        {
        if(uqIdfl[i-1]==0)
        {
            strcpy(uqIden[uqIdi++],mxIden[i-1]);
            for(j=i;j<mxIdeni;j++)
            {
            if(!strcmp(mxIden[j],mxIden[i-1]))
            {
                uqIdfl[j]=1;
            }
            }
        }
        }
        for(i=1;i<mxOpri+1;i++)
        {
        if(uqOpfl[i-1]==0)
        {
            strcpy(uqOpr[uqOpi++],mxOpr[i-1]);
            for(j=i;j<mxOpri;j++)
            {
            if(!strcmp(mxOpr[j],mxOpr[i-1]))
            {
                uqOpfl[j]=1;
            }
            }
        }
        }
        for(i=1;i<mxDeli+1;i++)
        {
        if(uqDefl[i-1]==0)
        {
            uqDel[uqDei++]=mxDel[i-1];
            uqDel[uqDei]='\0';
            for(j=i;j<mxDeli;j++)
            {
            if(mxDel[j]==mxDel[i-1])
            {
                uqDefl[j]=1;
            }
            }
        }
        }
    }

    void Sep_Val()
    {
        Opri=0;
        invToki=0;
        Ideni=0;
        Coni=0;
        Keyi=0;
        for(i=0;i<uqIdi;i++)
        {
        if(IsIden(uqIden[i][0]))
        {
            if(IsKey(uqIden[i]))
            {
            strcpy(Key[Keyi++],uqIden[i]);
            }
            else
            {
            ptfl=1;
            for(j=0;j<strlen(uqIden[i])&&ptfl;j++)
            {
                if(uqIden[i][j]=='.')
                {
                    strcpy(invalTok[invToki++],uqIden[i]);
                    ptfl=0;
                }
            }
            if(ptfl)
            {
                strcpy(Iden[Ideni++],uqIden[i]);
            }
            }
        }
        else
        {
            tfl=1;
            ptfl=0;
            for(j=0;j<strlen(uqIden[i])&&tfl;j++)
            {
            if(IsIden(uqIden[i][j]))
            {
                strcpy(invalTok[invToki++],uqIden[i]);
                tfl=0;
            }
            else if(uqIden[i][j]=='.')
            {
                if(ptfl)
                {
                    strcpy(invalTok[invToki++],uqIden[i]);
                    tfl=0;
                }
                if(!ptfl)
                {
                    ptfl=1;
                }
            }
            }
            if(tfl)
            {
            strcpy(Con[Coni++],uqIden[i]);
            }
        }
        }
        for(i=0;i<uqOpi;i++)
        {
        tfl=1;
        for(j=0;j<defOpi&&tfl;j++)
        {
            if(!strcmp(uqOpr[i],defOprStr[j]))
            {
            strcpy(Opr[Opri++],uqOpr[i]);
            tfl=0;
            }
        }
        if(tfl)
        {
            strcpy(invalTok[invToki++],uqOpr[i]);
        }
        }
    }

    void Display()
    {
        printf("\n\n\t: Lexical Analysis Report :\n\t%c Input String: %s\n\n\n",272,mStr);
        printf("\t%c Total Identifiers: %d\n",272,Ideni);
        for(i=0;i<Ideni;i++)
        {
        printf("\t\t");
        puts(Iden[i]);
        }
        printf("\n\t%c Total Constants: %d\n",272,Coni);
        for(i=0;i<Coni;i++)
        {
        printf("\t\t");
        puts(Con[i]);
        }
        printf("\n\t%c Total Literals: %d\n",272,Liti+cLiti);
        for(i=0;i<Liti;i++)
        {
        printf("\t\t");
        puts(Lit[i]);
        }
        for(i=0;i<cLiti;i++)
        {
        printf("\t\t");
        puts(cLit[i]);
        }
        printf("\n\t%c Total Keywords: %d\n",272,Keyi);
        for(i=0;i<Keyi;i++)
        {
        printf("\t\t");
        puts(Key[i]);
        }
        printf("\n\t%c Total Operators: %d\n",272,Opri);
        for(i=0;i<Opri;i++)
        {
        printf("\t\t");
        puts(Opr[i]);
        }
        printf("\n\t%c Total Delimeters: %d\n",272,uqDei);
        if(uqDei)
        {
        printf("\t\t");
        puts(uqDel);
        }
        printf("\n\t%c Total Invalid Tokens: %d\n",272,invToki+inToki);
        for(i=0;i<invToki;i++)
        {
        printf("\t\t");
        puts(invalTok[i]);
        }
        if(inToki)
        {
        for(i=0;i<strlen(inTok);i++)
        {
            printf("\t\t");
            printf("%c\n",inTok[i]);
        }
        }
        printf("\n\t%c Invalid Used Tokens: %d\n",272,Erri);
        for(i=0;i<Erri;i++)
        {
        printf("\t\t");
        puts(Err[i]);
        }
    }

};

void main()
{
clrscr();
FILE *fp;
    int size=0;
char file_name[40],ch;
char mystring[200];
printf("\n\n\tEnter File name: ");
gets(file_name);
fp=fopen(file_name,"r");
if(fp==NULL)
{
 perror("Error while opening the file.\n");
 exit(EXIT_FAILURE);
}
else
{
      fseek(fp, 0, SEEK_END);
  size = ftell(fp);
  fseek(fp, 0, SEEK_SET);
 while(( ch = fgetc(fp)) != EOF)
 {
   //printf("%c",ch);
   if(fgets (mystring , size , fp) != NULL )
   {
     //puts(mystring);//Here prints full file
     Lex_Ana oblex(mystring);//But here the last line going for lexical analysis
     oblex.Find_Lex();
     oblex.Rem_Dup();
     oblex.Sep_Val();
     oblex.Display();
     break;
   }
 }
}
fclose(fp);
getch();
}

任何人都可以解决这个问题..
编译器：Turbo c 3。

4

1 回答 1

1 
while(indata.eof())

它应该是

while(!indata.eof())

更好地使用

while(indata.getline(ch,800))

此外，在

{
 while(indata.eof())
 {
    indata>>ch;
 }
}
Lex_Ana oblex(ch);
    oblex.Find_Lex();
    oblex.Rem_Dup();
    oblex.Sep_Val();
    oblex.Display();

你为什么要重写到ch直到 eof？如果这样做，分析器只会分析文件的最后一个单词。

我想你想要这样的东西

while(indata.getline(ch,800))
{
    Lex_Ana oblex(ch);
    oblex.Find_Lex();
    oblex.Rem_Dup();
    oblex.Sep_Val();
    oblex.Display();
}
于 2012-06-06T10:46:47.653 回答