如何在OS中使用发电机查找功能，例如包装器

Question

我在python中具有一个函数，其功能为 find命令。因此，基本上它将进入深度，直到击中m_depth （MAXDEPTH），并且如果在ignore_dirs中指定的目录，则不会进入该目录。它将返回walk中找到的文件列表。该代码非常简单，并使用递归。

但是，对于大量文件或更大的深度，递归花费时间，返回时列表越来越大。因此，我正在寻找是否可以使用发电机，因此至少每次迭代的内存消耗少？

我尝试了yield结果，但是每当找到ignore_dirs时，它就会退出。

这是我拥有的代码：

def find(source_d, m_depth, ignore_dirs):
    '''
    This method does a recursive listing of files/directories from a given 
    path upto maximun recursion value provide as m_depth.
    :param source_d: Given source path to start the recursion from
    :param m_depth: Maximum recursion depth [determines how deep the method will traverse through the file system]
    :param ignore_dirs: this paths will not be traversed. List of strings. 
    '''
    def helper_find(path, ignore_dirs, m_depth, curr_depth=1):
        files = []
        if any(ignore_sub_dir == os.path.split(path)[-1] for ignore_sub_dir in ignore_dirs):
            return []
        if m_depth < curr_depth:
            return []
        else:
            things = os.listdir(path)
            for thing in things:
                if(os.path.isdir(os.path.join(path, thing))):
                    files.extend(helper_find(os.path.join(path, thing), ignore_dirs, m_depth, curr_depth+1))
                else:
                    files.append(os.path.join(path, thing))
        return files
    return helper_find(source_d, ignore_dirs, m_depth)

Answer 1

答案是肯定的，您可以使用yield from（仅在Python 3中使用）：

def find(source_d, m_depth, ignore_dirs):
    '''
    This method does a recursive listing of files/directories from a given
    path upto maximun recursion value provide as m_depth.
    :param source_d: Given source path to start the recursion from
    :param m_depth: Maximum recursion depth [determines how deep the method will traverse through the file system]
    :param ignore_dirs: this paths will not be traversed. List of strings.
    '''
    def helper_find(path, ignore_dirs, m_depth, curr_depth=1):
        if not any(ignore_sub_dir == os.path.split(path)[-1] for ignore_sub_dir in ignore_dirs)and m_depth >= curr_depth:
            things = os.listdir(path)
            for thing in things:
                if(os.path.isdir(os.path.join(path, thing))):
                    yield from helper_find(os.path.join(path, thing), ignore_dirs, m_depth, curr_depth+1)
                else:
                    yield os.path.join(path, thing)
    return helper_find(source_d, ignore_dirs, m_depth)