Text encoding: summary of results and times.
benr_mc at cogapp.com
Wed Sep 8 05:42:20 EDT 2021
On 07/09/2021 17:22, Bob Sneidar via use-livecode wrote:
> This makes sense to me (I think) because if I am not mistaken, UTF16 is Unicode, and UTF8 is simple ASCII. The slowdown from 6.7 to 7.0 was precicely the support for Unicode text. Someone will correct me if I am wrong about this. As a hobbyist, I try and stay away from localization issues. But I am interested in the idea that all text incoming should be text decoded and outgoing the inverse. (Did I get that right??)
Cue scenes of strong men reeling back in horror, ladies fainting, etc (Bateman
cartoons, for those of a British persuasion).
UTF16 is not Unicode, UTF8 is not simple ASCII, and I'm not even sure that the
slowdown from 6.7 to 7.0 was precisely the support for Unicode text, though
I'm not sure about that.
Unicode and ASCII are both conventions that assign character interpretations
to numbers. ASCII assigned approximately 94 character interpretations to the
numbers 32-126 (plus a few control interpretations to some other numbers).
WindowsLatin1, MacRoman, ISO-8859-1 etc all did the same but to a wider range
of numbers up to 255. Unicode does the same thing for a... much... larger
number of characters and glyphs, and hence using a... much... larger range of
Unicode specifies numbers, not bytes. UTF8 and UTF16 are two of several ways
of representing Unicode strings in bytes. UTF8 is designed to do so in a way
that makes ASCII text compatible with UTF8, i.e. a file of ASCII text is a
valid UTF8 file; the reverse is not necessarily true.
A long-running problem with Metacard, Revolution, LC up to v6 was being
surprisingly platform-centric about character sets. To this day, textEncode
etc only support MacRoman on Mac, only support ISO-8859-1 on Linux, and so on;
as if we never are on one platform, needing to deal with character streams
generated on another. See
LC7 brought LiveCode into the later part of the 20th century by properly
supporting Unicode, and by breaking the assumed link between bytes and
characters. However if I understand correctly, the internal format of strings
does not, or at least not necessarily, correspond to any externally defined
standard, but can take various forms in order to maximise efficiencies of
processing and storage.
Not sure if this helps, but it helped me to write it!
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