Question

安装PyReadline后，IPython无法正常工作。当我卸载它时，它再次开始工作。

ipython的堆栈跟踪：

(py2.7_monitor)[root@vm10-136-8-98 monitor]# ipython
WARNING: IPython History requires SQLite, your history will not be saved
Traceback (most recent call last):
  File "/home/py2.7_monitor/bin/ipython", line 11, in <module>
    sys.exit(start_ipython())
  File "/home/py2.7_monitor/lib/python2.7/site-packages/IPython/__init__.py", line 118, in start_ipython
    return launch_new_instance(argv=argv, **kwargs)
  File "/home/py2.7_monitor/lib/python2.7/site-packages/traitlets/config/application.py", line 591, in launch_instance
    app.initialize(argv)
  File "<string>", line 2, in initialize
  File "/home/py2.7_monitor/lib/python2.7/site-packages/traitlets/config/application.py", line 75, in catch_config_error
    return method(app, *args, **kwargs)
  File "/home/py2.7_monitor/lib/python2.7/site-packages/IPython/terminal/ipapp.py", line 314, in initialize
    self.init_shell()
  File "/home/py2.7_monitor/lib/python2.7/site-packages/IPython/terminal/ipapp.py", line 330, in init_shell
    ipython_dir=self.ipython_dir, user_ns=self.user_ns)
  File "/home/py2.7_monitor/lib/python2.7/site-packages/traitlets/config/configurable.py", line 380, in instance
    inst = cls(*args, **kwargs)
  File "/home/py2.7_monitor/lib/python2.7/site-packages/IPython/core/interactiveshell.py", line 531, in __init__
    self.init_readline()
  File "/home/py2.7_monitor/lib/python2.7/site-packages/IPython/core/interactiveshell.py", line 1941, in init_readline
    import IPython.utils.rlineimpl as readline
  File "/home/py2.7_monitor/lib/python2.7/site-packages/IPython/utils/rlineimpl.py", line 21, in <module>
    _rl = __import__(_rlmod_name)
  File "/home/py2.7_monitor/lib/python2.7/site-packages/readline.py", line 6, in <module>
    from pyreadline.rlmain import Readline
  File "/home/py2.7_monitor/lib/python2.7/site-packages/pyreadline/__init__.py", line 12, in <module>
    from . import logger, clipboard, lineeditor, modes, console
  File "/home/py2.7_monitor/lib/python2.7/site-packages/pyreadline/clipboard/__init__.py", line 13, in <module>
    from .win32_clipboard import GetClipboardText, SetClipboardText
  File "/home/py2.7_monitor/lib/python2.7/site-packages/pyreadline/clipboard/win32_clipboard.py", line 37, in <module>
    import ctypes.wintypes as wintypes
  File "/usr/local/lib/python2.7/ctypes/wintypes.py", line 23, in <module>
    class VARIANT_BOOL(_SimpleCData):
ValueError: _type_ 'v' not supported

Answer 1

As stated在其网站上，PyReadline库用于 Windows 。

查看堆栈跟踪的最后几行：

import ctypes.wintypes as wintypes
File "/usr/local/lib/python2.7/ctypes/wintypes.py", line 23, in <module>
class VARIANT_BOOL(_SimpleCData):
ValueError: _type_ 'v' not supported

它正试图从ctypes导入特定于Windows的数据类型，这显然是不可能的，因为您没有运行Windows。

Answer 2

这可能在2020年或之后完全没有帮助，但我想在此记录下来以供后代使用。

在HPC集群环境中安装Python 2.7.16时，我经历了相同的ValueError: _type_ 'v' not supported追溯，试图安装pdbpp，它取决于fancycompleter，后者取决于pyreadline，从2012年开始导入ctypes.wintypes并受此this core Python issue的影响。

的确，ctypes.wintypes绝对不能在非Windows平台上导入（Cygwin，MSYS2和Git Bash从技术上讲非Windows，因为它们将具有 real GNU Readline库，不需要纯粹的Python填充程序。

但是，如果是在非Windows平台上导入的，则由于上述问题，ctypes.wintypes会抛出ValueError而不是ImportError，这意味着由于未处理的异常，期望捕获try的典型except / ImportError会爆炸。

Pdbpp的fancycompleter或pyreadline在某种程度上成为了受害者。我对应该责怪谁感到困惑，因为fancycompleter的setup.py不应引入pyreadline作为依赖项except on Windows，但是在Linux系统上确实存在。并且如果在那，fancycompleter尝试导入它。

我能确定的是，我的点子缓存中可能有一个旧的fancycompleter，其setup.py中有一个错字，该错字在不应该的情况下拉入pyreadline，因为它是一次又一次地抓住这种依赖。

最终真正为我解决了这种情况的方法是先pip uninstall pyreadline，然后pip install -U --ignore-installed --no-cache-dir fancycompleter，以获得“新”版本的fancycompleter，该版本没有带来不必要的pyreadline依赖性。

安装PyReadline后出现“ValueError：_type_'v'不支持”错误

2 个答案: