# include "y2.h" 

defin( t, s )
register char * s;

{
  /*   define s to be a terminal if t=0
       or a nonterminal if t=1         */

  register val;

  # ifdef debug
  fprintf( ftable, "defin t = %d s = %s ", t, s );
  # endif 

  if ( t )
    {
      if ( ++nnonter >= NNONTERM )
        error( "too many nonterminals, limit %d", NNONTERM );
      nontrst[ nnonter ].name = cstash( s );
      # ifdef debug
      fprintf( ftable, "ret = %d\n", NTBASE + nnonter );
      # endif 
      return ( NTBASE + nnonter );
    }
    /* must be a token */
  if ( ++ntokens >= NTERMS )
    error( "too many terminals, limit %d", NTERMS );
  tokset[ ntokens ].name  = cstash( s );

  /* establish value for token */

  if ( s[ 0 ] == ' ' && s[ 2 ] == '\0' ) /* single character literal */
    val = s[ 1 ];
  else
    if ( s[ 0 ] == ' ' && s[ 1 ] == '\\' )
      {
        /* escape sequence */
        if ( s[ 3 ] == '\0' )
          {
            /* single character escape sequence */
            switch ( s[ 2 ] )
              {
                  /* character which is escaped */
                case 'n' :
                  val = '\n';
                  break ;
                case 'r' :
                  val = '\r';
                  break ;
                case 'b' :
                  val = '\b';
                  break ;
                case 't' :
                  val = '\t';
                  break ;
                case 'f' :
                  val = '\f';
                  break ;
                case '\'' :
                  val = '\'';
                  break ;
                case '"' :
                  val = '"';
                  break ;
                case '\\' :
                  val = '\\';
                  break ;
                default :
                  error( "invalid escape" );
              }
          }
        else
          if ( s[ 2 ] <= '7' && s[ 2 ] >= '0' )
            {
              /* \nnn sequence */
              if ( s[ 3 ] < '0' ||
                   s[ 3 ] > '7' ||
                   s[ 4 ] < '0' ||
                   s[ 4 ] > '7' ||
                   s[ 5 ] != '\0' )
                error( "illegal \\nnn construction" );
              val = 64 * s[ 2 ] + 8 * s[ 3 ] + s[ 4 ] - 73 * '0';
              if ( val == 0 )
                error( "'\\000' is illegal" );
            }
      }
    else
      {
        val = extval++;
      }
  tokset[ ntokens ].value = val;
  toklev[ ntokens ]       = 0;
  # ifdef debug
  fprintf( ftable, "ret = %d\n", ntokens );
  # endif 
  return ( ntokens );
}