CodePattern/A 代码模式/12 语言特性/1 类生成器/元类.py

from cppy.cp_util import *
from collections import Counter


# 定义一个带计数器的元类
class CounterMetaclass(type):

    def __new__(mcs, name, bases, attrs):
        attrs['_counter'] = Counter()
        return super().__new__(mcs, name, bases, attrs)


# 基于元类创建类
class Word(metaclass=CounterMetaclass):

    def __init__(self, word):
        self.word = word
        self._counter[self.word] += 1

    @classmethod
    def get_word_freqs(cls, n) -> Counter:
        return cls._counter.most_common(n)


for word in extract_file_words(testfilepath):
    Word(word)
print_word_freqs(Word.get_word_freqs(10))
'''
常用于将依赖项（如服务或配置）自动注入到类中。
'''