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类中的Python函数递归

[英]Python function recursion within a class

我做了下面的课。

class Message:

    def __init__(self, message):
        self.message = message
        self.__dict__.update(message)

    def dict_value_finder(self, field, partial_match=False):
        """It Takes a dict with nested lists and dicts,
        and searches all dicts for a key of the field
        provided and return the value(s) as a list.
        set partial_match = True to get partial matches.
        """
        fields_found = []

        for key, value in self.message.items():

            if field in key if partial_match else field == key:
                fields_found.append(value)
                print(key, value)

            elif isinstance(value, dict):
                results = dict_value_finder(value, field, partial_match)
                fields_found.extend(results)

            elif isinstance(value, list):
                for item in value:
                    if isinstance(item, dict):
                        more_results = dict_value_finder(item, field,
                                                         partial_match)
                        fields_found.extend(more_results)

        return fields_found

函数dict_value_finder将在类外部运行,如下所示:

def dict_value_finder(search_dict, field, partial_match=False):
    """Takes a dict with nested lists and dicts,
    and searches all dicts for a key of the field
    provided and return the value(s) as a list.
    set partial_match = True to get partial matches.
    """
    fields_found = []

    for key, value in search_dict.items():

        if field in key if partial_match else field == key:
            fields_found.append(value)
            print(key, value)

        elif isinstance(value, dict):
            results = dict_value_finder(value, field, partial_match)
            fields_found.extend(results)

        elif isinstance(value, list):
            for item in value:
                if isinstance(item, dict):
                    more_results = dict_value_finder(item, field,
                                                     partial_match)
                    fields_found.extend(more_results)

    return fields_found

但是,当我将其放入类中时,会出现错误:

  File "<ipython-input-42-76ab838299bc>", line 23, in dict_value_finder
    results = dict_value_finder(value, field, partial_match)

NameError: name 'dict_value_finder' is not defined

我不确定该如何将函数添加到类中,因为它需要递归。

results = dict_value_finder(value, field, partial_match)更改为此:

results = self.dict_value_finder(value, field, partial_match)

more_results = dict_value_finder(item, field,partial_match)可以:

more_results = self.dict_value_finder(item, field,partial_match)

为了访问类实例的属性,我们应该使用self

解决评论中的问题:

def dict_value_finder(self, field, partial_match=False, search=None):

    fields_found = []

    search =  search or self.message

    for key, value in search.items():

        if field in key if partial_match else field == key:
            fields_found.append(value)
            print(key, value)

        elif isinstance(value, dict):
            results = self.dict_value_finder(field, partial_match, value)
            fields_found.extend(results)

        elif isinstance(value, list):
            for item in value:
                if isinstance(item, dict):
                    more_results = self.dict_value_finder(field,partial_match, item)
                    fields_found.extend(more_results)

    return fields_found

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