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This topic created in 4967 days ago, the information mentioned may be changed or developed.
listA = [{'ID'=14, ...},
{'ID'=15, ...},
...,
]
写一个简单好看的表达式，如果listA里面有'ID'==14的字典，就返回True?
{'ID'=15, ...},
...,
]
写一个简单好看的表达式，如果listA里面有'ID'==14的字典，就返回True?
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1
skyleft Sep 24, 2012  1
y=lambda listA:bool([x for x in listA if x['ID']==14])
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2
reus Sep 24, 2012
any(map(lambda d: d.get('ID', None) == 14, l))
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3
013231 Sep 24, 2012 2
any(item['id'] == 14 for item in listA)
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4
reus Sep 24, 2012 1
这个比刚才的更快，因为是generator，遇到为True的就直接返回了，不用遍历整个list
any(d for d in l if d.get('ID', None) == 14) 比如l = [{'ID': 14}] * 5000000，用这个会秒回，map的话慢很多= = |
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7
013231 Sep 24, 2012
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9
Veelian Sep 24, 2012
你确定list里是字典？
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