Question

请勿尝试为以下代码找到一些合理的解释。只是简单地重现案例。问题是我得到了一个包含在另一个异常中的异常，而我只期待其中一个异常。 Python代码如下：

class TEST(object):
    def __init__(self, param, content=[]):
        self.param = param
        self.content = content

    def test_rec(self):
        try:
            collection = ''.join([c.test_rec() for c in self.content])
        except Exception as e:
            raise Exception('Exception [%s] in %s' % (e, self.__class__))
        return collection+self.param

class TEST2(TEST):
    pass

a = TEST('1')
b = TEST2('2')
c = TEST2('3')
a.content = [b, c]
b.content = 1

print a.test_rec()

目前的例外是：

Exception: Exception [Exception ['int' object is not iterable] in <class '__main__.TEST2'>] in <class '__main__.TEST'>

预期是：

Exception: Exception ['int' object is not iterable] in <class '__main__.TEST2'>

Answer 1

当您添加其他打印语句时，您会看到会发生什么：

def test_rec(self):
    try:
        collection = ''.join([c.test_rec() for c in self.content])
    except Exception as e:
        print(e)
        raise Exception('<%s> in %s' % (e, self.__class__))
    return collection+self.param

print语句给出：

'int' object is not iterable
<'int' object is not iterable> in <class '__main__.TEST2'>

最后的例外是

Exception: <<'int' object is not iterable> in <class '__main__.TEST2'>> in <class '__main__.TEST'>

a.test_rec() - ＆gt; b.test_rec();这引发了异常，抓住它并重新加注它。这反过来被a.test_rec()抓住并重新加注。

Answer 2

这是解决方案。有点难看，但它有效：

class MyException(Exception):
    pass

class TEST(object):
    def __init__(self, param, content=[]):
        self.param = param
        self.content = content

    def test_rec(self):
        try:
            collection = ''.join([c.test_rec() for c in self.content])
        except MyException:
            raise
        except Exception as e:
            raise MyException('Exception [%s] in %s' % (e, self.__class__))
        return collection+self.param

class TEST2(TEST):
    pass

a = TEST('1')
b = TEST2('2')
c = TEST2('3')
a.content = [b, c]
b.content = 1

print a.test_rec()

python上的重复异常

2 个答案: