[Python-3000] Support for PEP 3131

[Rauli Ruohonen]

On 6/3/07, Jim Jewett <jimjjewett at gmail.com> wrote:
> On 6/2/07, Rauli Ruohonen <rauli.ruohonen at gmail.com> wrote:
> > # identifier_charset: 0-7f
>
> Why not ASCII?
> Why not be more specific, with 0x30-0x39, 0x41-0x5a, 0x5f, 0x61-0x7a
>
> When adding characters, this isn't such a problem.  When restricting
> them, a standard spelling is more important.

I followed Stephen Turnbull's convention of only adding additional
restrictions to those already provided by PEP 3131. Here 0-7f would
block out all non-7-bit characters, and within that range the PEP
rule is "Within the ASCII range (U+0001..U+007F), the valid characters
for identifiers are the same as in Python 2.5."

> > #!/usr/bin/env python
> >
> > # Real code.
>
> > This isn't really anything more than a countermeasure against Ka-Ping's
> > tricky.py -exploit
>
> uhh... I don't see any charset comment there, so his coding: with a
> non-ASCII letter in "coding" would still work.

If it came in the comments before the first empty line, then it would cause a
syntax error, because non-ASCII wouldn't be allowed there to prevent such
trickery. The "first empty line" rule was there to make the safe area visually
clear to the reader.