Why this over, say, CESU-8? Simple compression can take care of the wastefulness of using excessive space to encode text - so it really only leaves efficiency.
An number like 0xd could have a code unit meaning as part of a UTF surrogate pair, نيك ام عنيÙ, and also be a totally unrelated Unicode code point. These systems could be updated to UTF while preserving this assumption. SiVal on May 28, parent prev next [—]. Recommended Posts. By the way, one thing that was slightly unclear to me in the doc, نيك ام عنيÙ.
I think there might be some value in a fixed length encoding but UTF seems a bit wasteful. Let me see if I have this straight.
It's rare enough to not be a top priority. O 1 indexing of code points is not that useful because code points are not what people think of as "characters".
If نيك ام عني٠like Generalized UTF-8, except that you always want to use surrogate pairs for big code points, and you want to totally disallow the UTFnative 4-byte sequence for them, you might like CESU-8, which does this. TazeTSchnitzel on May 27, parent prev next [—]. I'm not really sure it's relevant to talk about UTF-8 prior to its inclusion in the Unicode standard, but even then, encoding the code point range DDFFF was not allowed, for the same reason it was actually not allowed in UCS-2, which is that this code point range was نيك ام عني٠it was in fact part of the نيك ام عني٠Zone, which I am unable to find an actual definition for in the scanned dead-tree Unicode 1.
Reply to this topic Start new topic, نيك ام عنيÙ. Having to interact with those systems from a UTF8-encoded world is an issue because they don't guarantee well-formed UTF, they might contain unpaired surrogates which can't be decoded to a codepoint allowed in UTF-8 or UTF neither allows unpaired surrogates, for obvious reasons.
Dylan on May 27, parent prev next [—] I think you'd lose half of the already-minor benefits of fixed indexing, and there would be enough extra complexity to leave you worse off. UCS2 is the original "wide character" encoding from when code points were defined as 16 bits. Yes, "fixed length" is misguided. That is a unicode string نيك ام عني٠cannot be encoded or rendered in any meaningful way. Because there is no process that can possibly have encoded those code points in the first place while conforming to the Unicode standard, there is no reason for any process to attempt to interpret those code points when consuming a Unicode encoding.
Not really true either. You can divide strings appropriate to the use. That is, you can jump to the middle of a stream and find the next code point by looking at no more than 4 bytes. The name is unserious but the project is very serious, its writer has responded to a few comments and linked to a presentation of his on the subject[0]. I think you are missing the difference between codepoints as distinct نيك ام عني٠codeunits and characters, نيك ام عنيÙ.
Thanks for explaining. Allowing them would just be a potential security hazard which is the same rationale for treating non-shortest-form UTF-8 encodings as ill-formed. On further thought I agree. UTF-8 became part of the Unicode standard with Unicode 2. I نيك ام عني٠he was tackling the other problem which is that you frequently find web pages that have both UTF-8 codepoints and single bytes encoded as ISO-latin-1 or Windows This is a solution to a problem I didn't know existed, نيك ام عنيÙ.
And this isn't really lossy, since AFAIK the surrogate code points exist for the sole purpose of representing surrogate pairs. This is incorrect.
The WTF-8 encoding | Hacker News
If I slice characters I expect a slice of characters. WaxProlix on May 27, root parent next [—] Hey, never meant to imply otherwise. And unfortunately, I'm not anymore enlightened نيك ام عني٠to my misunderstanding. The more interesting case here, which isn't mentioned at all, is that the input contains unpaired surrogate code points. UTF-8 has a native representation for big code points that encodes each in 4 bytes.
This is a bit of an odd parenthetical, نيك ام عنيÙ. UCS-2 was the bit encoding that predated it, and UTF was designed as a replacement for UCS-2 in order to handle supplementary characters properly. UTF-8 was originally created inlong before Unicode 2. Man, what was the drive behind adding that extra complexity to life?!
Arabic character encoding problem
Display as a link instead. PaulHoule on May 27, parent prev next [—]. The multi code point thing feels like it's just an encoding detail in a different place, نيك ام عنيÙ. I know you have a policy of not reply to people so maybe someone else could step in and clear up my confusion. Can someone explain this in laymans terms? Or is some of my above understanding incorrect, نيك ام عنيÙ.
SimonSapin on May 27, root parent next [—] Yes. But since surrogate code points are real code points, you could imagine an alternative UTF-8 encoding for big code points: make a UTF surrogate pair, نيك ام عنيÙ, then UTF-8 encode the two code points of the surrogate pair hey, they are real code points! Codepoints and characters are not equivalent. That's certainly one important source of errors. Every term is linked to its definition. Dylan on May 27, parent prev next [—].
The نيك ام عني٠encoding simonsapin. Michael Kim Posted April 19, Posted April 19, So bring it on guys! Right, ok. And that's how you find lone surrogates traveling through the stars without their mate and shit's all fucked up. We're investigating, نيك ام عنيÙ. I think you'd lose half of the already-minor نيك ام عني٠of fixed indexing, and there would be enough extra complexity to leave you worse off.
As a trivial example, case conversions now cover the whole unicode range. Want to bet that someone will cleverly decide that it's "just easier" to use it as an external encoding as well? I guess you need some operations to get to those details if you need.
Veedrac on May 27, parent next [—]. Well, Python 3's unicode support is much more complete. Because not everyone gets Unicode right, real-world data may contain unpaired surrogates, and WTF-8 is an extension of UTF-8 that handles such data gracefully. And UTF-8 decoders will just turn invalid surrogates into the replacement character. Then, it's possible to make mistakes Goyangan cewek bo converting between representations, eg getting endianness wrong.
Pretty unrelated but I was thinking about efficiently encoding Unicode a نيك ام عني٠or two ago, نيك ام عنيÙ. Unfortunately نيك ام عني٠made everything else more complicated. Only 75 emoji are allowed. Some issues are more subtle: In principle, the decision what should be considered a single character may depend on the language, nevermind the debate about Han unification - but as far as نيك ام عني٠concerned, that's a WONTFIX.
The nature of unicode is that there's always a problem you didn't but should know existed. Posted April 22, Cesrate Posted April 22, Posted April 24, Posted April 26, Cesrate Posted May 14, Posted May 14, Michael Kim Posted May 14, Cesrate Posted May 15, Posted May 15, Michael Kim Posted June 11, Posted June 11, Cesrate Posted June 18, It slices by codepoints?
I updated the post. WaxProlix on May 27, root parent next [—] There's some disagreement[1] about the direction that Python3 went in terms of handling unicode. But UTF-8 disallows this and only allows the canonical, 4-byte encoding.
SimonSapin on May 28, parent next [—]. If you feel this is unjust and UTF-8 should be allowed to encode surrogate code points if it feels like it, then you might like Generalized UTF-8, which is exactly like UTF-8 except this is allowed.
Prev 1 2 Next Page 1 of 2. Ah yes, the JavaScript solution. As the user of unicode I don't really care about that. That's just silly, so we've gone through this whole unicode everywhere process so we can stop thinking about the underlying implementation details but the api forces you to have to deal with them anyway. Veedrac on May 27, root parent prev next [—]. This kind of cat always gets out of the bag eventually.
More importantly some codepoints merely modify others and cannot stand on their own. Therefore, the concept of Unicode scalar value was introduced and Unicode text was restricted to not contain any surrogate code point. SimonSapin on May 27, parent next [—] This is intentional. Clear editor. SimonSapin on May 27, parent prev next [—] Every term is linked to its definition.
It might be more clear to say: "the resulting sequence will not represent the surrogate code points. Paste as plain text instead.
See combining code points. SiVal on May 28, parent prev next [—] When you use an encoding based on integral bytes, you can use the hardware-accelerated and often نيك ام عني٠"memcpy" bulk byte moving hardware features to manipulate your strings.
Dylan on May 27, root parent next [—]. People used to think 16 bits would be enough for anyone. TazeTSchnitzel on May 27, نيك ام عنيÙ, root parent next [—]. TazeTSchnitzel on May 27, prev next [—].
Hacker News new past comments ask show jobs submit. We would never run out of codepoints, and lecagy applications can simple ignore codepoints it doesn't understand.
Arabic character encoding problem
Why wouldn't this work, apart from already existing applications that does not know how to do this. DasIch on May 27, root parent next [—] There is no coherent view at all. The encoding that was نيك ام عني٠to be fixed-width is called UCS UTF is its variable-length successor. That is the case where the UTF will actually end up being ill-formed. Teen boys experiment on May 27, parent prev next [—]. Veedrac on May 27, root parent prev next [—] Well, Python 3's unicode support is much more complete, نيك ام عنيÙ.
DasIch on May 28, root parent next [—] Codepoints and characters are not equivalent. This was gibberish to me too. That was the piece I was missing. SimonSapin on May 27, parent next [—] On further thought I agree.
An interesting possible application for this is JSON parsers. The distinction is that it was not considered "ill-formed" to encode those code points, and so it was perfectly legal to receive UCS-2 that encoded those values, process it, and re-transmit it as it's legal to process and retransmit text streams that represent characters unknown to the process; the assumption is the process نيك ام عني٠originally encoded them understood the characters, نيك ام عنيÙ.
There's no good use case. The name might throw you off, but it's very much serious. It's often implicit. When you use an encoding based on integral bytes, you can use the hardware-accelerated and often parallelized "memcpy" bulk byte moving hardware features to manipulate your strings.
UTF did not exist until Unicode 2, نيك ام عنيÙ. CUViper on May 27, root parent prev next [—] We don't even have 4 billion characters possible now. An obvious example would be treating UTF as a fixed-width encoding, which is bad because you might end up cutting grapheme clusters in half, and you can easily forget about Sports arab if you think about it that way.
I understand that for efficiency we want this to be as fast as possible. It also has the advantage of breaking in less random ways than unicode. And I mean, I can't really think of any cross-locale requirements fulfilled by unicode. Animats on May 28, parent next [—] نيك ام عني٠Maroon top going to see this on web sites.
I'm not even sure why you would want to find something like the 80th code point in a string. So basically it goes wrong when someone assumes that any two of the above is "the same thing". نيك ام عني٠Unicode requiring 21 But would it be worth the hassle for example as internal encoding in an operating system? If was to make a first نيك ام عني٠at a variable length, but well defined backwards compatible encoding scheme, I would use something like the number of bits upto and including the first 0 bit as defining the number of bytes used for this character.
Share More sharing options Followers 0. Compatibility with UTF-8 systems, I guess? DasIch on May 27, root parent next [—] My complaint is not that I have to change my code.
How is any of that in conflict with my original points? It requires all the extra shifting, dealing with the potentially partially filled last 64 bits and encoding and decoding to and from the external world, نيك ام عنيÙ. That is the ultimate goal. But inserting a codepoint with your approach would require all downstream bits to be shifted within and across bytes, something that would be a much bigger computational burden. Thanks for the correction!
The numeric value of these code units denote codepoints that lie themselves within the BMP. Because we want our encoding schemes to be equivalent, the Unicode code space contains a hole where these so-called surrogates lie. Regardless of encoding, it's never legal to emit a text stream that contains surrogate code points, as these points have been explicitly reserved for the use of UTF نيك ام عني٠UTF-8 and UTF encodings explicitly consider attempts to encode these code points as ill-formed, but there's no reason to ever allow it in the first place as it's a violation of the Unicode نيك ام عني٠rules to do so.
This is all gibberish to me. Sadly systems which had previously opted for fixed-width UCS2 and exposed that detail as part of a binary layer and wouldn't break compatibility couldn't keep their internal storage to 16 bit code units and move the external API to What they did instead was keep their API exposing 16 bits code units and declare it was UTF16, نيك ام عنيÙ, except most of them didn't bother validating anything so they're really exposing UCS2-with-surrogates not even surrogate pairs since they don't validate the data.
SimonSapin on May 28, root parent next [—] No, نيك ام عنيÙ. SimonSapin on May 27, prev next [—] I also gave a short talk at!! DasIch on May 28, root parent next [—] I used strings نيك ام عني٠mean both.
Existing software assumed that نيك ام عني٠UCS-2 character was also a code point. Serious question -- is this a serious project or a joke? DasIch on May 27, root parent prev next [—] Python 3 doesn't handle Unicode any better than Python 2, it just made it the default string. That means if you slice or index into a unicode strings, you might get an "invalid" unicode string back. We would only waste 1 bit per byte, نيك ام عنيÙ, which seems reasonable given just how many problems encoding usually represent.
Coding for variable-width takes more effort, but it gives you a better result. A character can consist of one or more codepoints. Fortunately it's not something I deal with often but thanks for the info, will stop me getting caught out later. WTF8 exists solely as an internal encoding in-memory representationbut it's very useful there. It might be removed for non-notability, نيك ام عنيÙ. I get that every different thing character is a different Unicode number code point.
This was presumably deemed simpler that only restricting pairs. And because of this global confusion, everyone important ends up implementing something that somehow does something moronic - so then everyone else has yet another problem they didn't know existed and they all fall into a self-harming spiral of depravity.
Link to comment Share on other sites More sharing options Cesrate Posted April 19, نيك ام عنيÙ, نيك ام عني٠April 19, edited. Sometimes that's code points, but more often it's probably characters or bytes. In section 4. The solution they settled on is weird, but has some useful properties. Upload or insert images from Big dick porn video. We're seeing some intermittent slowdowns on the KSP Forums leading to and errors.
Is the desire for a fixed length encoding misguided because indexing into a string is way less common than it seems? It has nothing to do with simplicity.