Ada*_*ski 27 python namedtuple python-3.x
我想在内部使用namedtuples,但我希望保持与给我一个普通元组的用户的兼容性.
from collections import namedtuple
tuplePi=(1,3.14,"pi") #Normal tuple
Record=namedtuple("MyNamedTuple", ["ID", "Value", "Name"])
namedE=Record(2, 2.79, "e") #Named tuple
namedPi=Record(tuplePi) #Error
TypeError: __new__() missing 2 required positional arguments: 'Value' and 'Name'
tuplePi.__class__=Record
TypeError: __class__ assignment: only for heap types
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Mar*_*ers 43
您可以使用*args调用语法:
namedPi = Record(*tuplePi)
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这将tuplePi序列的每个元素作为单独的参数传递.
您还可以使用namedtuple._make()类方法将任何序列转换为实例:
namedPi = Record._make(tuplePi)
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演示:
>>> from collections import namedtuple
>>> Record = namedtuple("MyNamedTuple", ["ID", "Value", "Name"])
>>> tuplePi = (1, 3.14, "pi")
>>> Record(*tuplePi)
MyNamedTuple(ID=1, Value=3.14, Name='pi')
>>> Record._make(tuplePi)
MyNamedTuple(ID=1, Value=3.14, Name='pi')
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