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191
lib/lex.ncform
Normal file
191
lib/lex.ncform
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/* #pragma lib "libl.a" */
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int yylineno =1;
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# define YYU(x) x
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char yytext[YYLMAX];
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struct yysvf *yylstate [YYLMAX], **yylsp, **yyolsp;
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Uchar yysbuf[YYLMAX];
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Uchar *yysptr = yysbuf;
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int *yyfnd;
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extern struct yysvf *yyestate;
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int yyprevious = YYNEWLINE;
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# ifdef LEXDEBUG
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extern void allprint(char);
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# endif
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int
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yylook(void){
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struct yysvf *yystate, **lsp;
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struct yywork *yyt;
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struct yysvf *yyz;
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int yych;
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struct yywork *yyr;
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# ifdef LEXDEBUG
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int debug;
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# endif
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Uchar *yylastch;
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/* start off machines */
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# ifdef LEXDEBUG
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debug = 0;
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# endif
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if (!yymorfg)
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yylastch = (Uchar*)yytext;
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else {
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yymorfg=0;
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yylastch = (Uchar*)yytext+yyleng;
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}
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for(;;){
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lsp = yylstate;
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yyestate = yystate = yybgin;
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if (yyprevious==YYNEWLINE) yystate++;
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for (;;){
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# ifdef LEXDEBUG
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if(debug)fprintf(yyout,"state %d\n",yystate-yysvec-1);
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# endif
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yyt = yystate->yystoff;
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if(yyt == yycrank){ /* may not be any transitions */
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yyz = yystate->yyother;
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if(yyz == 0)break;
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if(yyz->yystoff == yycrank)break;
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}
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*yylastch++ = yych = input();
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tryagain:
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# ifdef LEXDEBUG
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if(debug){
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fprintf(yyout,"char ");
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allprint(yych);
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putchar('\n');
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}
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# endif
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yyr = yyt;
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if ( (int)yyt > (int)yycrank){
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yyt = yyr + yych;
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if (yyt <= yytop && yyt->verify+yysvec == yystate){
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if(yyt->advance+yysvec == YYLERR) /* error transitions */
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{unput(*--yylastch);break;}
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*lsp++ = yystate = yyt->advance+yysvec;
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goto contin;
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}
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}
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# ifdef YYOPTIM
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else if((int)yyt < (int)yycrank) { /* r < yycrank */
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yyt = yyr = yycrank+(yycrank-yyt);
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# ifdef LEXDEBUG
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if(debug)fprintf(yyout,"compressed state\n");
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# endif
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yyt = yyt + yych;
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if(yyt <= yytop && yyt->verify+yysvec == yystate){
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if(yyt->advance+yysvec == YYLERR) /* error transitions */
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{unput(*--yylastch);break;}
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*lsp++ = yystate = yyt->advance+yysvec;
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goto contin;
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}
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yyt = yyr + YYU(yymatch[yych]);
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# ifdef LEXDEBUG
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if(debug){
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fprintf(yyout,"try fall back character ");
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allprint(YYU(yymatch[yych]));
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putchar('\n');
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}
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# endif
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if(yyt <= yytop && yyt->verify+yysvec == yystate){
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if(yyt->advance+yysvec == YYLERR) /* error transition */
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{unput(*--yylastch);break;}
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*lsp++ = yystate = yyt->advance+yysvec;
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goto contin;
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}
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}
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if ((yystate = yystate->yyother) && (yyt= yystate->yystoff) != yycrank){
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# ifdef LEXDEBUG
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if(debug)fprintf(yyout,"fall back to state %d\n",yystate-yysvec-1);
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# endif
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goto tryagain;
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}
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# endif
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else
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{unput(*--yylastch);break;}
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contin:
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# ifdef LEXDEBUG
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if(debug){
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fprintf(yyout,"state %d char ",yystate-yysvec-1);
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allprint(yych);
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putchar('\n');
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}
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# endif
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;
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}
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# ifdef LEXDEBUG
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if(debug){
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fprintf(yyout,"stopped at %d with ",*(lsp-1)-yysvec-1);
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allprint(yych);
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putchar('\n');
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}
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# endif
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while (lsp-- > yylstate){
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*yylastch-- = 0;
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if (*lsp != 0 && (yyfnd= (*lsp)->yystops) && *yyfnd > 0){
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yyolsp = lsp;
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if(yyextra[*yyfnd]){ /* must backup */
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while(yyback((*lsp)->yystops,-*yyfnd) != 1 && lsp > yylstate){
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lsp--;
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unput(*yylastch--);
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}
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}
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yyprevious = YYU(*yylastch);
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yylsp = lsp;
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yyleng = yylastch-(Uchar*)yytext+1;
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yytext[yyleng] = 0;
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# ifdef LEXDEBUG
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if(debug){
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fprintf(yyout,"\nmatch '%s'", yytext);
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fprintf(yyout," action %d\n",*yyfnd);
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}
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# endif
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return(*yyfnd++);
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}
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unput(*yylastch);
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}
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if (yytext[0] == 0 /* && feof(yyin) */)
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{
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yysptr=yysbuf;
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return(0);
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}
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yyprevious = input();
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yytext[0] = yyprevious;
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if (yyprevious>0)
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output(yyprevious);
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yylastch = (Uchar*)yytext;
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# ifdef LEXDEBUG
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if(debug)putchar('\n');
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# endif
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}
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return(0); /* shut up the compiler; i have no idea what should be returned */
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}
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int
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yyback(int *p, int m)
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{
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if (p==0) return(0);
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while (*p)
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{
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if (*p++ == m)
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return(1);
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}
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return(0);
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}
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/* the following are only used in the lex library */
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int
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yyinput(void){
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if(yyin == ((void*)0))
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yyin = stdin;
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return(input());
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}
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void
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yyoutput(int c)
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{
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if(yyout == ((void*)0))
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yyout = stdin;
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output(c);
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}
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void
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yyunput(int c)
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{
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unput(c);
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}
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