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Re: ???strict??? strings?

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Dan Book
January 7, 2020 04:31
Re: ???strict??? strings?
Message ID:
On Mon, Jan 6, 2020 at 11:24 PM Felipe Gasper <>

> > On Jan 6, 2020, at 10:27 PM, Dan Book <> wrote:
> >
> > On Mon, Jan 6, 2020 at 10:15 PM Felipe Gasper <>
> wrote:
> > But anyway, there’s no problem left to solve. Now that I see an example
> of `perlunitut`’s workflow not working as I thought (decode() doesn’t set
> UTF8 if the string is plain ASCII), I see why this won’t work. As I wrote a
> bit ago, humble pie.
> >
> > I'd like to try to fix any misconceptions presented in such docs, but
> looking at perlunitut, the only mention of the UTF8 flag is the vague
> description of the internal format you shouldn't concern yourself with. The
> document appears entirely correct, though it is mostly talking about usage
> of text and binary strings (something you have to know in any language),
> and not the Perl implementation details we're discussing. Did you perhaps
> mean a different document?
> I did mean perlunitut, actually.
> I thought all explicit decode()s would set the UTF8 flag. That’s true for
> Latin-1, but not for UTF-8/utf8/utf-8 when the string is pure ASCII. It
> didn’t occur to me that there’d potentially be a difference between Latin-1
> and UTF-8, so I just didn’t try it. I don’t know why there *is* a
> difference :), but I’m sure there’s a good reason.
> The apparent fact that what Sereal and CBOR intend to do--distinguish
> between text and binary strings--can’t reliably be done in Perl via
> introspection, despite the presence of two widely-used encoders
> (Sereal::Encoder and CBOR::XS) that attempt, via the UTF8 flag, to do
> precisely that was/is also a point of confusion.
> It would have helped me if I’d seen somewhere--and maybe this is already
> there but just in someplace that I missed--that all decode() operations do
> not alter the string’s internal state differently, perhaps even with the
> UTF-8 versus Latin-1 example.

I don't see what this has to do with perlunitut as it doesn't reference the
string's internal state or the UTF8 flag at all, beyond the vague paragraph
I mentioned. This sort of information belongs in perlunicode or
perluniintro, which each have sections discussing these implementation


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