连接空字典中的元组

Question

errors = {}

#errorexample
errors['id'] += ('error1',)
errors['id'] += ('error2',)

#works but ugly
errors['id'] = ('error1',)
errors['id'] += ('error2',)

如果'error1'不存在，则会失败。我真的需要扩展dict吗？

Answer 1

使用collections.defaultdict而不是普通的dict - 毕竟，这种方便性正是引入default-dict类型的原因：

>>> import collections
>>> errors = collections.defaultdict(tuple)
>>> errors['id'] += ('error1',)
>>> errors['id'] += ('error2',)
>>> errors['id']
('error1', 'error2')

Answer 2

import collections
errors = collections.defaultdict(tuple)

Answer 3

>>> from collections import defaultdict
>>> errors = defaultdict (tuple)
>>> errors['id'] += ('blargh',)
>>> errors['id']
('blargh',)