python - 从生成器函数内部导出重复的代码

Question

遵循以下方法:

def _locate(self, text):
        """
        This method accesses preceding locators if these exist, it then calls an overridable helper method called _relocate
        which receives text with readjusted boundaries and searches inside, the basic implemented behaviour is that of a logical or
        """
        if not self.precedents:
            for sub_segment in self._relocate(text, Segment(0, len(text), 1)):
                if self._multiple:
                    yield sub_segment
                elif self.max_segment.prob > self._prob_threshold:
                    yield self.max_segment
                    return
        else:
            for precedent in self.precedents:
                for segment in precedent.locate(text):
                    for sub_segment in self._relocate(text, segment):
                        if self._multiple:
                            yield sub_segment
                        elif self.max_segment.prob > self._prob_threshold:
                            yield self.max_segment
                            return

        # if we haven't found a good enough segment return the best one we came across while locating
        if not self._multiple:
            yield self.max_segment

它有一些重复两次的代码:

for sub_segment in self._relocate(text, segment):
    if self._multiple:
        yield sub_segment
    elif self.max_segment.prob > self._prob_threshold:
        yield self.max_segment
        return

我天真地认为我可以定义一个辅助方法并只使用一次代码，因此开始实现它，但是，事实证明这几乎是不可能的(因为代码同时使用了产量和返回)并导致了我在代码长度和运行时间方面带来的更多痛苦是值得的。

不确定我到底在问什么(如果有什么问题的话，我可能会问是否有人知道共享生成器代码的通用方法，或者看看如何在这里完成此操作？)，但无论如何随着生成器主题的发展，我发现这段经历非常有说服力且有趣，所以我想分享一下。

Answer 1

我认为您可以通过在循环外部定义段生成器来删除代码重复

def _locate(self, text):
        """
        This method accesses preceding locators if these exist, it then calls an overridable helper method called _relocate
        which receives text with readjusted boundaries and searches inside, the basic implemented behaviour is that of a logical or
        """
        if self.precedents:
            segments = (seg for precedent in self.precedents for seg in precedent.locate(text))
        else:
            segments = (Segment(0, len(text), 1),)

        for segment in segments:
            for sub_segment in self._relocate(text, segment):
                if self._multiple:
                    yield sub_segment
                elif self.max_segment.prob > self._prob_threshold:
                    yield self.max_segment
                    return

        # if we haven't found a good enough segment return the best one we came across while trying
        if not self._multiple:
            yield self.max_segment