Micro Python -- a lean and efficient implementation of Python 3
wxjmfauth at gmail.com
wxjmfauth at gmail.com
Tue Jun 10 05:13:25 EDT 2014
Le mardi 10 juin 2014 09:32:34 UTC+2, wxjm... at gmail.com a écrit :
> Le mercredi 4 juin 2014 13:53:19 UTC+2, Robin Becker a écrit :
>
> > On 04/06/2014 12:01, Tim Chase wrote:
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> >
>
> > > On 2014-06-04 00:58, Paul Rubin wrote:
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> >
>
> > >> Steven D'Aprano <steve at pearwood.info> writes:
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> >
>
> > >>>> Maybe there's a use-case for a microcontroller that works in
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> >
>
> > >>>> ISO-8859-5 natively, thus using only eight bits per character,
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> >
>
> > >>> That won't even make the Russians happy, since in Russia there
>
> >
>
> > >>> are multiple incompatible legacy encodings.
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> >
>
> > >>
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> >
>
> > >> I've never understood why not use UTF-8 for everything.
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> >
>
> > >
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> >
>
> > > If you use UTF-8 for everything, then you end up in a world where
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> >
>
> > > string-indexing (see ChrisA's other side thread on this topic) is no
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> >
>
> > > longer an O(1) operation, but an O(N) operation. Some of us slice
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> >
>
> > > strings for a living. ;-) I understand that using UTF-32 would allow
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> >
>
> > > us to maintain O(1) indexing at the cost of every string occupying 4
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> >
>
> > > bytes per character. The FSR (again, as I understand it) allows
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> >
>
> > > strings that fit in one-byte-per-character to use that, scaling up to
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> >
>
> > > use wider characters internally as they're actually needed/used.
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> >
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> > >
>
> >
>
> > ........
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> >
>
> > I believe that we should distinguish between glyph/character indexing and string
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> >
>
> > indexing. Even in unicode it may be hard to decide where a visual glyph starts
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> >
>
> > and ends. I assume most people would like to assign one glyph to one unicode,
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> >
>
> > but that's not always possible with composed glyphs.
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> >
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> >
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> >
>
> > >>> for a in (u'\xc5',u'A\u030a'):
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> >
>
> > ... for o in (u'\xf6',u'o\u0308'):
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> >
>
> > ... u=a+u'ngstr'+o+u'm'
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> >
>
> > ... print("%s %s" % (repr(u),u))
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> >
>
> > ...
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> >
>
> > u'\xc5ngstr\xf6m' Ångström
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> >
>
> > u'\xc5ngstro\u0308m' Ångström
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> >
>
> > u'A\u030angstr\xf6m' Ångström
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> >
>
> > u'A\u030angstro\u0308m' Ångström
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> >
>
> > >>> u'\xc5ngstr\xf6m'==u'\xc5ngstro\u0308m'
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> >
>
> > False
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> >
>
> >
>
> >
>
> > so even unicode doesn't always allow for O(1) glyph indexing. I know this is
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> >
>
> > artificial, but this is the same situation as utf8 faces just the frequency of
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> >
>
> > occurrence is different. A very large amount of computing is still western
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> >
>
> > centric so searching a byte string for latin characters is still efficient;
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> >
>
> > searching for an n with a tilde on top might not be so easy.
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> >
>
> > --
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> >
>
> > Robin Becker
>
>
>
> =========
>
>
>
> Python succeeded to become an anti-unicode product!
>
>
>
> jmf
-----
And deeply buggy!
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