我想采用任意数量的路径来表示嵌套的tar档案,并对最里面的档案执行 *** 作.问题是,嵌套可以是任意的,因此我需要的上下文管理器的数量也是任意的.
举个例子:
ARCHIVE_PATH = "path/to/archive.tar"INNER_PATHS = ( "nested/within/archive/one.tar","nested/within/archive/two.tar",# Arbitary number of these)def List_inner_contents(archive_path,inner_paths): with Tarfile(archive_path) as tf1: with Tarfile(fileobj=tf1.extractfile(inner_paths[0])) as tf2: with Tarfile(fileobj=tf2.extractfile(inner_paths[1])) as tf3: # ...arbitary level of these! return tfX.getnames()contents = List_inner_contents(ARCHIVE_PATH,INNER_PATHS))
我不能使用with语句的nesting syntax,因为可以有任意数量的级别来嵌套.我不能使用contextlib.nested
因为文档在那里说:
…using
nested()
to open two files is a programming error as the first file will not be closed promptly if an exception is thrown when opening the second file.
有没有办法使用语言结构来执行此 *** 作,还是需要手动管理我自己的打开文件对象堆栈?最佳答案对于这种情况,您可以使用递归.对于这种情况来说感觉最自然(当然如果在Python中没有特殊处理):
ARCHIVE_PATH = "path/to/archive.tar"INNER_PATHS = [ "nested/within/archive/one.tar",# Arbitary number of these]def List_inner_contents(archive_path,inner_paths): def rec(tf,rest_paths): if not rest_paths: return tf.getnames() with Tarfile(fileobj=tf.extractfile(rest_paths[0])) as tf2: return rec(tf2,rest_paths[1:]) with Tarfile(archive_path) as tf: try: return rec(tf,inner_paths) except RuntimeError: # We come here in case the inner_paths List is too long # and we go too deeply in the recursion return None
总结 以上是内存溢出为你收集整理的如何嵌套任意数量的Python文件上下文管理器?全部内容,希望文章能够帮你解决如何嵌套任意数量的Python文件上下文管理器?所遇到的程序开发问题。
如果觉得内存溢出网站内容还不错,欢迎将内存溢出网站推荐给程序员好友。
欢迎分享,转载请注明来源:内存溢出
评论列表(0条)