static double factor()

in interpreters/minibasic/basic.c [1748:2021]

• 246 lines of code
• 40 McCabe index (conditional complexity)

static double factor(void)
{
  double answer = 0;
  FAR char *str;
  FAR char *end;
  int len;

  switch (g_token)
    {
    case OPAREN:
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      break;

    case VALUE:
      answer = getvalue(g_string, &len);
      match(VALUE);
      break;

    case MINUS:
      match(MINUS);
      answer = -factor();
      break;

    case FLTID:
      answer = variable();
      break;

    case DIMFLTID:
      answer = dimvariable();
      break;

    case E:
      answer = exp(1.0);
      match(E);
      break;

    case PI:
      answer = acos(0.0) * 2.0;
      match(PI);
      break;

    case SIN:
      match(SIN);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      answer = sin(answer);
      break;

    case COS:
      match(COS);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      answer = cos(answer);
      break;

    case TAN:
      match(TAN);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      answer = tan(answer);
      break;

    case LN:
      match(LN);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      if (answer > 0)
        {
          answer = log(answer);
        }
      else
        {
          seterror(ERR_NEGLOG);
        }
      break;

    case POW:
      match(POW);
      match(OPAREN);
      answer = expr();
      match(COMMA);
      answer = pow(answer, expr());
      match(CPAREN);
      break;

    case SQRT:
      match(SQRT);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      if (answer >= 0.0)
        {
          answer = sqrt(answer);
        }
      else
        {
          seterror(ERR_NEGSQRT);
        }
      break;

    case ABS:
      match(ABS);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      answer = fabs(answer);
      break;

    case LEN:
      match(LEN);
      match(OPAREN);
      str = stringexpr();
      match(CPAREN);
      if (str)
        {
          answer = strlen(str);
          free(str);
        }
      else
        {
          answer = 0;
        }
      break;

    case ASCII:
      match(ASCII);
      match(OPAREN);
      str = stringexpr();
      match(CPAREN);
      if (str)
        {
          answer = *str;
          free(str);
        }
      else
        {
          answer = 0;
        }
      break;

    case ASIN:
      match(ASIN);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      if (answer >= -1 && answer <= 1)
        {
          answer = asin(answer);
        }
      else
        {
          seterror(ERR_BADSINCOS);
        }
      break;

    case ACOS:
      match(ACOS);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      if (answer >= -1 && answer <= 1)
        {
          answer = acos(answer);
        }
      else
        {
          seterror(ERR_BADSINCOS);
        }
      break;

    case ATAN:
      match(ATAN);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      answer = atan(answer);
      break;

    case INT:
      match(INT);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      answer = floor(answer);
      break;

    case RND:
      match(RND);
      match(OPAREN);
      answer = expr();
      match(CPAREN);
      answer = integer(answer);
      if (answer > 1)
        {
          answer = floor(rand() / (RAND_MAX + 1.0) * answer);
        }
      else if (answer == 1)
        {
          answer = rand() / (RAND_MAX + 1.0);
        }
      else
        {
          if (answer < 0)
            {
              srand((unsigned)-answer);
            }

          answer = 0;
        }
      break;

    case VAL:
      match(VAL);
      match(OPAREN);
      str = stringexpr();
      match(CPAREN);
      if (str)
        {
          answer = strtod(str, 0);
          free(str);
        }
      else
        {
          answer = 0;
        }
      break;

    case VALLEN:
      match(VALLEN);
      match(OPAREN);
      str = stringexpr();
      match(CPAREN);
      if (str)
        {
          strtod(str, &end);
          answer = end - str;
          free(str);
        }
      else
        {
          answer = 0.0;
        }
      break;

    case INSTR:
      answer = instr();
      break;

    default:
      if (isstring(g_token))
        {
          seterror(ERR_TYPEMISMATCH);
        }
      else
        {
          seterror(ERR_SYNTAX);
        }
      break;
    }

  while (g_token == SHRIEK)
    {
      match(SHRIEK);
      answer = factorial(answer);
    }

  return answer;
}