19 lines
776 B
Python
19 lines
776 B
Python
from collections import Iterable
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if __name__ == '__main__':
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# 将复杂的序列扁平化，使用递归来脱壳
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def flatten(items, ignore=(str, bytes)):
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for item in items:
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# 要进行递归，首先这个元素要是可迭代的，其次它不能是字符串或二进制串
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if isinstance(item, Iterable) and not isinstance(item, ignore):
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# yield from 将请求转发到flatten函数返回的迭代器进行嵌套，避免再写for循环
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# yield from 在后面的协程和基于生成器的并发程序里有重要作用
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yield from flatten(item, ignore)
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else:
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yield item
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a = [1, 2, [3, 4, [5, 6], 7], 8]
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for item in flatten(a):
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print(item)
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