36 lines
1.1 KiB
Python
36 lines
1.1 KiB
Python
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# 可迭代对象分解
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def iterable_breakdown(list):
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# 如果可迭代对象长度大于接数据的变量数量，分解值过多报错
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length = list.__len__()
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length = 20
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# 这样会报错，因为list长度是20，但分解变量只有两个
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x, y = list
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# 想要接住任意长度的列表，需要用*
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# *x是包含list前n-1个元素的列表，y是最后一个元素
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# 我们可以在任意位置接入带*的参数来接住一些值，这些值会在*变量中以列表存储
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*x, y = list
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x, *y, z = list
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# 假设有一个变长元组序列
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record = [("foo",1,2),("bar","suka"),("foo",2,4)]
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def do_foo(x,y):
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print(x,y)
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def do_bar(s):
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print(s)
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# 我们可以使用*来解包从而将参数薅出来
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for tag, *args in record:
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if tag == "foo":
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do_foo(*args)
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elif tag == "bar":
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do_bar(*args)
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# 同理，也可以用*变量来占位挖掉不要的变量，比如在特定位置用*ignore或*_来挖掉参数
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