Python深度合并字典数据
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原文地址: http://stackoverflow.com/questions/20656135/
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Python deep merge dictionary data
提问by evolution
Is there a library in Python that I can use to deep merge dictionaries:
Python 中是否有一个库可用于深度合并字典：
The following:
下列：
a = { 'first' : { 'all_rows' : { 'pass' : 'dog', 'number' : '1' } } }
b = { 'first' : { 'all_rows' : { 'fail' : 'cat', 'number' : '5' } } }
When i combine I want this to look like:
当我结合时，我希望它看起来像：
a = { 'first' : { 'all_rows' : { 'pass' : 'dog', 'fail' : 'cat', 'number' : '5' } } }
采纳答案by vincent
I hope I don't reinvent the wheel but the solution is fairly short. And, superfun to code.
我希望我不要重新发明轮子，但解决方案很短。而且，编码超级有趣。
def merge(source, destination):
"""
run me with nosetests --with-doctest file.py
>>> a = { 'first' : { 'all_rows' : { 'pass' : 'dog', 'number' : '1' } } }
>>> b = { 'first' : { 'all_rows' : { 'fail' : 'cat', 'number' : '5' } } }
>>> merge(b, a) == { 'first' : { 'all_rows' : { 'pass' : 'dog', 'fail' : 'cat', 'number' : '5' } } }
True
"""
for key, value in source.items():
if isinstance(value, dict):
# get node or create one
node = destination.setdefault(key, {})
merge(value, node)
else:
destination[key] = value
return destination
So the idea is to copy the source to the destination, and every time it's a dict in the source, recurse. So indeed you will have a bug if in A a given element contains a dict and in B any other type.
所以这个想法是将源复制到目标，并且每次它是源中的字典时，递归。因此，如果在 A 中给定元素包含一个 dict 而在 B 中包含任何其他类型，则确实会出现错误。
[EDIT] as said in comments the solution was already here : https://stackoverflow.com/a/7205107/34871
[编辑] 正如评论中所说，解决方案已经在这里：https: //stackoverflow.com/a/7205107/34871
