[Jython-users] chr/unichr question

[Robert W. B. <rb...@di...>]

Hello all,

I have a question about the builtins chr().  The Python Library
Reference for 2.1b2 says it "Return a string of one character whose ASCII
code is the integer i, e.g., chr(97) returns the string 'a'. This is the
inverse of ord(). The argument must be in the range [0..255], inclusive;
ValueError will be raised if i is outside that range."

When interpreting this for Jython, the obvious catches are that it
specifies "range [0..255]", and raises ValueError for i outsite this
range.

This doesn't really seem to apply considering how Jython only has the
2-byte character string.  Different behavior for Jython's builtin chr()
makes sense.  However, is this difference in chr() official?  I didn't
see a comment on http://jython.sourceforge.net/docs/differences.html about
this, and I wanted to be sure before committing it to paper for a Jython
publication (and risking a ValueError being raised in Jython2.1final or
2.2).

Here's code in case I don't make any sense above:

CPython:
>>>chr(256)
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
ValueError: chr() arg not in range(256)

Jython:
>>>chr(256)
u'\u0100'

Thanks,
Robert