如何使 python StreamWriter 需要 unicode 输入？

发布于 2024-12-09 13:16:25 字数 625 浏览 0 评论 0原文

python 编解码器模块提供了 StreamWriter 类，用于透明地编码输出流。例如：

outstream = codecs.getwriter('utf8')(sys.__stdout__)
outstream.write(u'\u2713')
outstream.write(' A-OK!\n') # I want this to fail!
outstream.close()

然而，我对默认 StreamWriter 的问题是它会排除 str 对象和 unicode 对象。如果我的程序正在向该流写入 str，那么这是一个错误，我希望它失败！有没有一种方法可以实现这一点，而无需编写自己的 StreamWriter 来强制写入对象的类型？

另外，我不希望我的解决方案对 sys.stdout.encoding、sys.stdout.isatty()、locale.getpreferredencoding()< 敏感/code>、sys.getfilesystemencoding()、os.environ["PYTHONIOENCODING"] 或 python 试图变得聪明的任何其他方式。

原文

The python codecs module provides StreamWriter classes for transparently encoding output streams. For instance:

outstream = codecs.getwriter('utf8')(sys.__stdout__)
outstream.write(u'\u2713')
outstream.write(' A-OK!\n') # I want this to fail!
outstream.close()

However the problem I have with the default StreamWriter is that it will except str objects as well as unicode objects. If my program is writing a str to this stream, it is a bug and I want it to fail! Is there a way to make this happen without writing my own StreamWriter that enforces the type of objects written?

Also, I don't want my solution to be sensitive to sys.stdout.encoding, sys.stdout.isatty(), locale.getpreferredencoding(), sys.getfilesystemencoding(), os.environ["PYTHONIOENCODING"] or whatever other ways python has of trying to be clever.

分享到QQ

分享到微博

如果你对这篇内容有疑问，欢迎到本站社区发帖提问参与讨论，获取更多帮助，或者扫码二维码加入 Web 技术交流群。

发布评论

需要登录才能够评论，你可以免费注册一个本站的账号。

dawn曙光 2024-12-16 13:16:25

如果可能的话，请执行您在 Python 3 中尝试执行的操作，Python 3 在 unicode 和 bytes 之间有更强的区别。如果做不到这一点，您需要子类化 StreamWriter，例如：

import codecs

class StrictUTF8Writer(codecs.StreamWriter):
    '''A StreamWriter for utf8 that requires written objects be unicode'''
    encode = codecs.utf_8_encode

    def write(self, object):
        if not isinstance(object, unicode):
            raise ValueError('write() requires unicode object')
        return codecs.StreamWriter.write(self, object)

If possible, do what you're trying to do in Python 3, which has a much stronger distinction between unicode and bytes. Failing that, you'll need to subclass StreamWriter, for example:

import codecs

class StrictUTF8Writer(codecs.StreamWriter):
    '''A StreamWriter for utf8 that requires written objects be unicode'''
    encode = codecs.utf_8_encode

    def write(self, object):
        if not isinstance(object, unicode):
            raise ValueError('write() requires unicode object')
        return codecs.StreamWriter.write(self, object)

回复收藏 0 原文

~没有更多了~