external/bsd/byacc/dist/test/ok_syntax1.y

   1 /*      $NetBSD: ok_syntax1.y,v 1.1.1.1 2015/01/03 22:58:23 christos Exp $      */
   2
   3 %pure_parser
   4
   5 %parse_param { int regs[26] }
   6 %parse_param { int *base }
   7
   8 %lex_param { int *base }
   9
  10 %{
  11 # include <stdio.h>
  12 # include <ctype.h>
  13
  14 #ifdef YYBISON
  15 #define YYSTYPE int
  16 #define YYLEX_PARAM base
  17 #define YYLEX_DECL() yylex(YYSTYPE *yylval, int *YYLEX_PARAM)
  18 #define YYERROR_DECL() yyerror(int regs[26], int *base, const char *s)
  19 int YYLEX_DECL();
  20 static void YYERROR_DECL();
  21 #endif
  22
  23 %}
  24
  25 %start list
  26
  27 %token DIGIT LETTER
  28
  29 %token OCT1 '\177'
  30 %token HEX1 '\xff'
  31 %token HEX2 '\xFF'
  32 %token HEX3 '\x7f'
  33 %token STR1 "\x7f\177\\\n"
  34 %token STR2 "\x7f\
  35 \177\\\n"
  36
  37 %token BELL '\a'
  38 %token BS   '\b'
  39 %token NL   '\n'
  40 %token LF   '\f'
  41 %token CR   '\r'
  42 %token TAB  '\t'
  43 %token VT   '\v'
  44
  45 %union
  46 {
  47     char *      cval;
  48     int         ival;
  49     double      dval;
  50 }
  51
  52 %0 '@'
  53 %2 '~'
  54 %> '^'
  55 %< '#'
  56
  57 %left '|'
  58 %left '&'
  59 %left '+' '-'
  60 %left '*' '/' '%'
  61 %left UMINUS   /* supplies precedence for unary minus */
  62
  63 %% /* beginning of rules section */
  64
  65 list  :  /* empty */
  66       |  list stat '\n'
  67       |  list error '\n'
  68             {  yyerrok ; }
  69       ;
  70
  71 stat  :  expr
  72             {  printf("%d\n",$<ival>1);}
  73       |  LETTER '=' expr
  74             {  regs[$<ival>1] = $<ival>3; }
  75       ;
  76
  77 expr  :  '(' expr ')'
  78             {  $<ival>$ = $<ival>2; }
  79       |  expr '+' expr
  80             {  $<ival>$ = $<ival>1 + $<ival>3; }
  81       |  expr '-' expr
  82             {  $<ival>$ = $<ival>1 - $<ival>3; }
  83       |  expr '*' expr
  84             {  $<ival>$ = $<ival>1 * $<ival>3; }
  85       |  expr '/' expr
  86             {  $<ival>$ = $<ival>1 / $<ival>3; }
  87       |  expr '%' expr
  88             {  $<ival>$ = $<ival>1 % $<ival>3; }
  89       |  expr '&' expr
  90             {  $<ival>$ = $<ival>1 & $<ival>3; }
  91       |  expr '|' expr
  92             {  $<ival>$ = $<ival>1 | $<ival>3; }
  93       |  '-' expr %prec UMINUS
  94             {  $<ival>$ = - $<ival>2; }
  95       |  LETTER
  96             {  $<ival>$ = regs[$<ival>1]; }
  97       |  number
  98       ;
  99
 100 number:  DIGIT
 101          {  $<ival>$ = $<ival>1; (*base) = ($<ival>1==0) ? 8 : 10; }
 102       |  number DIGIT
 103          {  $<ival>$ = (*base) * $<ival>1 + $<ival>2; }
 104       ;
 105
 106 %% /* start of programs */
 107
 108 #ifdef YYBYACC
 109 extern int YYLEX_DECL();
 110 #endif
 111
 112 int
 113 main (void)
 114 {
 115     int regs[26];
 116     int base = 10;
 117
 118     while(!feof(stdin)) {
 119         yyparse(regs, &base);
 120     }
 121     return 0;
 122 }
 123
 124 #define UNUSED(x) ((void)(x))
 125
 126 static void
 127 YYERROR_DECL()
 128 {
 129     UNUSED(regs); /* %parse-param regs is not actually used here */
 130     UNUSED(base); /* %parse-param base is not actually used here */
 131     fprintf(stderr, "%s\n", s);
 132 }
 133
 134 int
 135 YYLEX_DECL()
 136 {
 137         /* lexical analysis routine */
 138         /* returns LETTER for a lower case letter, yylval = 0 through 25 */
 139         /* return DIGIT for a digit, yylval = 0 through 9 */
 140         /* all other characters are returned immediately */
 141
 142     int c;
 143
 144     while( (c=getchar()) == ' ' )   { /* skip blanks */ }
 145
 146     /* c is now nonblank */
 147
 148     if( islower( c )) {
 149         yylval->ival = (c - 'a');
 150         return ( LETTER );
 151     }
 152     if( isdigit( c )) {
 153         yylval->ival = (c - '0') % (*base);
 154         return ( DIGIT );
 155     }
 156     return( c );
 157 }