Re: Using inherited attributes within a yacc grammar

Inherited attributes can be used in Yacc by pushing them onto the
semantic stack just before the appearance of the nonterminal on the
rhs In your example it looks like this:


number
      :
          'x'
          {
                $$ = 16; /* integer.base = 16 */
          }
          integer
          {
                $$ = $3; /* number.value = integer.value */
          }
      |
          {
                $$ = 10; /* integer.base = 10 */
          }
          integer
      ;


integer
      :
          digit
          {
                $$ = $1; /* integer1.value = digit.value */
          }
      |
          {
                $$ = $0; /* integer2.base = integer1.base */
          }
          integer
          digit
          {
                $$ = $2 * $0 + $3;
                      /* integer1.value = integer2.value * integer1.base + digit.value */
          }


      ;


digit
      :
          "0"
          {


                $$ = 0; /* digit.value = 0 */
          }
      |
          .
          .
          .
      |
          "f"
          {


                $$ = 15; /* digit.value = 15 */
          }
      ;


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