To replicate, in Python 3.1 on Linux (utf-8 console):

>>> print(chr(0x9000))
退

Copy and paste this character into the prompt. It appears correctly (as a Chinese character). Then:

>>> import readline
>>> readline.parse_and_bind('"\M-i":"    "')

Now try to paste the character again: it appears as "    ��"
 (four spaces, two unknown character symbols), and if you press return, you get a SyntaxError.

This happens with all characters beginning with \xe9: In UTF-8, that's 0x9000-0x9fff. If the terminal encoding is changed to cp1252, I'm told that the same thing can be achieved with é, which is \xe9 there.

You're binding the M-i keyboard sequence. Could it be that the \xe9 byte is translated by the terminal to M-i, and that causes the interference? In this case, it's not really a bug.

Original bug report: https://github.com/ipython/ipython/issues/58

I confirm that the issue exists, but I don't think that it comes from Python. I bet that the readline library uses *byte* string, not *character* string, and so is unable to handle correctly multibyte characters like the chinese character U+9000.

Yes, this is a readline issue.

Add '"\M-i":"    "' line to ~/.inputrc, run 'rlwrap cat' command, paste this multibyte character and you got the same result.

This is not a Python bug.

OK, thanks, and sorry for the noise. I've closed this issue.

Looking at the readline manual, it looks like this is tied up with the options input-meta, output-meta and convert-meta. Fiddling around with .inputrc hasn't clarified exactly what they do, but it seems that the terminal can either handle unicode, or shortcuts involving meta (alt), but not both.