32 lines
875 B
Python
32 lines
875 B
Python
import re
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import reprlib
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RE_WORD = re.compile('\w+')
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class Sentence:
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def __init__(self, text):
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self.text = text
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self.words = RE_WORD.findall(text)
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def __repr__(self):
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return 'Sentence(%s)' % reprlib.repr(self.text)
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def __iter__(self):
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return SentenceIterator(self.words) # 迭代协议要求__iter__返回一个迭代器
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class SentenceIterator:
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def __init__(self, words):
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self.words = words
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self.index = 0
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def __next__(self):
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try:
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word = self.words[self.index] # 获取 self.index 索引位（从0开始）上的单词。
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except IndexError:
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raise StopIteration() # 如果 self.index 索引位上没有单词，那么抛出 StopIteration 异常
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self.index += 1
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return word
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def __iter__(self):
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return self # 返回迭代器本身 |