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Re: pack and ASCII

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Eric Brine
January 15, 2012 13:42
Re: pack and ASCII
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On Sat, Jan 14, 2012 at 11:11 AM, Jesse Luehrs <> wrote:

> On Sat, Jan 14, 2012 at 02:47:07AM -0500, Eric Brine wrote:
> > I said C<pack> should always downgrade its output. I was most definitely
> > including C<< pack "N/A*" >> and C<< pack "N/A*" >> in my statement.
> >
> > So yes, you did ask me if I meant that the output of C<< pack "N" >>
> should
> > be encoded.
> >
> > And no, that would be stupid.
> But this is *exactly* my point. There is no useful behavior that
> pack('N/A*', $text) can do at all. If the resulting string has the UTF8
> flag set, then the length will be interpreted as part of the utf8
> sequence, which is broken. If it doesn't, then the text will be a
> utf8-encoded byte string, which is also broken. If pack chooses one of
> the two of those behaviors based on whether or not $text has non-ASCII
> characters in it, that's orders of magnitude worse. The only way for
> this to be correct is if this format is only ever passed an
> already-encoded byte string, and the result is also treated as a byte
> string. Passing non-ASCII characters to pack (or at least, to a format
> like 'A') should be caught as an error *when you do that*, not just
> something that does the wrong thing silently.

I agree with everything you said here.

- Eric

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