用$var得到不同的结果!~ ?/?

我正在分析一个XML文件,在提取了一些信息之后,我想看看一个特定的字段中是否有一个“/”(斜杠)。所以我执行以下代码:

  if (defined($orgUIDLookup{$orgUidMid}))
  {
    my $country = $orgUIDLookup{$orgUidMid};
    print "country = $country ";
    if ($country !~ ?/?)
    {
      print "OK\n";
      $airportRef{country} = $country;
    }
    else
    {
      print "no good\n";
      $needHelp = 1;
    }
  }

grep '^country = .*/' foo
country = CN/MA/RE no good
country = CN/MA/RE OK
country = CN/MA/RE OK
country = CN/MA/RE OK
country = RB/MJ OK
country = RB/MJ OK
country = RB/MJ OK
country = CN/MA/RE OK
country = CN/MA/RE OK
country = RB/MJ OK
country = RB/MJ OK
country = CN/MA/RE OK
country = CN/MA/RE OK
country = RB/MJ OK
country = RB/MJ OK
country = KR/TV OK
country = KR/TV OK
country = KR/TV OK
country = WS/AQ OK
country = AA/NT OK
country = AA/NT OK
country = AA/NT OK
country = AA/NT OK
country = AA/NT OK
country = AA/NT OK

为什么这个测试会通过 else 第一次分支可以,但是通过 if 每隔一次分支?