Georgian Capital letters added to Unicode. Now what?

Last may Unicode approved 46 Capital letters of Georgian Mkhedruli alphabet.

Maybe it’s a bit early, but operating systems will support this change in future anyway. Out of curiosity I decided to do a little research about what will change for us – developers and I’m sharing it in this article.

Few definitions just in case:
Unicode – A standard, which maps every symbol with an unique number. Also it describes specific rules for different languages. This standard is used all over the technical world and everyone who needs text processing / representing, follows it – Operating systems, platforms, browsers…

UTF-8 – Unicode has the list of symbols and number codes, but it does not care how this information will be stored in memory. There are various encoding algorithms for this. UTF-8 is one of the most popular ones as it optimally uses memory and does not require extra bytes for a symbol which can be fit in just one. Other encoding examples are UCS-2, UTF-16, UTF-32…

Changes in a standard cause changes in implementations, which does not happen immediately. For instance, ₾ Georgian currency symbol was added to 8 version of Unicode on 17 may, 2015 and the Windows update for this symbol was released on 19 January, 2016.

Operating Systems should update keyboard drivers to enable Georgian users use CAPS mode to write Capital letters (there are 33 letters in Georgian, so shift+symbols method is already taken). Also system fonts should be updated, so correct symbols will appear during the font fallback.

Due to the fact, that the Capital and Small versions of the same letter have different codes, software developers usually need some considerations – up until now only for other languages, now for Georgian, too. For instance, when it’s necessary to compare strings, search, match regex patterns, sort, store into the database, etc.

 

Database

MS SQL server has built in Unicode support and during the operations it follows the standard anyway. Just make sure it follows the correct version: SQL Fiddle

It’s different with MySQL – Here each database, table or even a column might have corresponding collation defined, based on what kind of information it stores. We are accustomed to using utf8_general_ci, as it ‘processes’ Georgian letters, too. This collation does not completely implement the Unicode unlike utf8_unicode_ci. Generally, it was being used just because of better performance, however, there is not much difference with modern processors. utf8_unicode_ci will correctly process new Georgian alphabet upon version upgrade.

Here is an example:
Together with the unique codes, Unicode also defines the order of symbols, which is used during sorting. E.g. in this list all kinds of Georgian letter ‘ა’ are listed together – Nuskhuri, Asomtavruli and Mkhedruli. Then versions of ‘ბ’ letter appear. Probably new capital letters will be added in the same way.

SQL Fiddle

CREATE TABLE IF NOT EXISTS `test` (
  `content` varchar(200) NOT NULL
) DEFAULT CHARSET=utf8 COLLATE utf8_general_ci;
INSERT INTO `test` (`content`) VALUES
  ('აბგ'),  ('ააააა'),  ('Ⴁააააა'),  ('Ⴀააააა'),  ('bcd'),  ('ab.'),  ('Ⴄ'),  ('ж'),  ('Ж'),  ('ц'),  ('Ц');
  

CREATE TABLE IF NOT EXISTS `test_better` (
  `content` varchar(200) NOT NULL
) DEFAULT CHARSET=utf8 COLLATE utf8_unicode_ci;
INSERT INTO `test_better` (`content`) VALUES
  ('აბგ'),  ('ააააა'),  ('Ⴁააააა'),  ('Ⴀააააა'),  ('bcd'),  ('ab.'),  ('Ⴄ'),  ('ж'),  ('Ж'),  ('ц'),  ('Ц');


select * from `test` d order by d.content;
select * from `test_better` d order by d.content;

Result:

ab., bcd, Ж, ж, ц, Ц, Ⴀააააა, Ⴁააააა, Ⴄ, ააააა, აბგ
ab., bcd, ж, Ж, ц, Ц, ააააა, Ⴀააააა, აბგ, Ⴁააააა, Ⴄ

The MySQL 8 beta release, which appeared currently, has implemented Unicode version 9, our capital letters are in version 11 🙂

 

Javascript

Although there are many implementations, we can’t ignore V8 anyway, so I’ll discuss based on it.

Javascript has Unicode support, but some things still have problems (e.g. unicode regex). If we need sorting or filtering on our site, than ordinary sort won’t work any more and we should use Locale. Then it will consider Unicode rules. For instance:

let a = ['აბგ','ააააა','Ⴁააააა','Ⴀააააა','bcd','ab.','Ⴄ','ж','Ж','ц','Ц'];
console.log(a.sort());
console.log(a.sort(Intl.Collator('ru').collate));

Unfortunately it does not have support for Georgian collation at all. So, we cannot correctly sort together with Nuskhuri and Asomtavruli. Well, this is a very rare case anyway, so no need to worry. Casual function sorts based on the code points, so it will be according to alphabet (with the exception of capital letters).

That problem with capitals can be solved by converting strings to the same case. Giorgi suggested an idea:

myArray.sort(function(s1,s2){ return s1.toLowerCase() > s2.toLowerCase()}));

Probably it will work correctly for Georgian, too, after V8 renews the Unicode implementation. Currently it works like that for Asomtavruli and Nuskhuri: "Ⴀ".toLowerCase() => "ⴀ"

It seems that, as standard defined Asomtavruli as CAPITAL and Nuskhuri as SMALL, these alphabets are implemented as cases of single one instead of being two completely different alphabets. (v8 source file: unicode.cc, code points are mapped directly.)
Now Mkhedruli is caseless. It’s interesting how it will be marked. I think there is no other language with two kinds of Capital letters.
Anyway, this requires the version upgrade anyway.

Now I remembered, that V8 is an open source project and a volunteer can add Georgian locale. For the time being this results in an empty array:

Intl.Collator.supportedLocalesOf('ka')

 

Java

Java is not in a hurry to upgrade either. JDK 9 with the Unicode 8 implementation (where Lari currency symbol was added) was released after two years – September of 2017.
Here the strings are compared with ‘equals’. In future we’ll need to use the ‘equalsIgnoreCase’ method for Georgian, too:

"Ⴀ".equals("ⴀ")  => false
"Ⴀ".equalsIgnoreCase("ⴀ")  => true

As there is one Capital alphabet already, I’m testing with it. We just don’t use that alphabet generally.

Also, we can’t search with regex directly. Ordinary i – ignore case flag does not work, as Unicode is processed differently. So, we should write:

"A".matches("(?i)[a]")  => true
"Ⴀ".matches("(?i)[ⴀ]") => false

Pattern.compile("[ⴀ]", Pattern.CASE_INSENSITIVE | Pattern.UNICODE_CASE).matcher("Ⴀ").matches();  => true

Correspondingly, we should consider this wherever we use strings – maps, sets, etc.

 

PHP

Generally, working with unicode strings is not pleasant in PHP at all + more conversions will be added here, too.

 

 
We’ll also need change at other place – with very convenient search tools – grep and the similar ones. The case insensitive option of grep does not work for existing Georgian Asomtavruli capital alphabet even now. I hope the Unicode changes will be reflected in their upgrades, too. They are great apps for regex filtering and searching in large (or small) texts and files.

Many of Georgian application systems won’t be able to quickly upgrade their platforms, as testing would take huge amount of time. They will probably add some conversions and validations in front-end, to prevent user input capital strings from appearing in old Java or other systems.

Overall, I like that Capital letters were added (as a result of several persons hard work). It’s an important part of the Georgian language and should not be lost.

Do you have any ideas, what else will need to be changed?

Some resources about the topic:
On.ge – UNICODE-მა ქართული მხედრული ანბანის 46 მთავრული ასონიშანი დაამტკიცა
DevFest 2016: Akaki Razmadze –  ❤  [I LOVE UNICODE]
DevFest 2017: Akaki Razmadze – გუტენბერგი, სტივ ჯობსი, გუგლი, ხინკალი, უნიკოდი
DevFest 2016: Michael Everson – The confusing case history of Georgian in Unicode

Memory optimization with multidimensional arrays in Java

Yesterday I hit a memory limit while submitting a problem solution to an online judge. All because I used a wrong declaration of a multidimensional array. In case of C or C++ language this would not be a problem, but due to the fact that in Java everything is an object (despite primitive types), we should calculate allocated memory differently for multidimensional arrays.

For instance, in C++ the size of this array is 96 bytes (assuming we have 4-byte int):
int arr[2][3][4];
2 * 3 * 4 = 24. Plus 4 bytes for each due to int type and we get total of 24 * 4 = 96.
If we declare the array like this, result would be the same: int arr[4][3][2]

Let’s compare these two declarations in Java:
int arr[][][] = new int[40000][200][2];
int arr[][][] = new int[2][200][40000];

There is not much different from the data storage viewpoint, however the first one requires much more memory. Here is why:
1. Array in Java is an object itself. Every object (not near the reference, but in the heap) holds few additional bytes for the object header information. This header contains data necessary for the VM, which later uses it for the garbage collector or some other purposes. As far as I know, generally it takes 8 bytes in case of a 32-bit machine and 16 bytes in case of a 64-bit one. Apart from this, an object holds information about the array size – that’s additional 4 bytes. Also padding in memory might take few more bytes. So, I won’t start precise calculations and let’s assume that each array object (excluding array elements) takes X bytes.

2. int[a][b] – In Java language this is ‘a’ number of arrays which contain ‘b’ number of elements. I.e. we have a+1 number of objects instead of just one.
int[a][b][k] In case of a three-dimensional one a * b + a + 1 number of object, etc.

Now let’s calculate and compare sizes of these arrays:
(40,000 * 200 + 40,000 + 1) * X + (40,000 * 200 * 2 * 4)
(2 * 200 + 2 + 1) * X + (40,000 * 200 * 2 * 4)

Clearly, the second part, which calculates the total size of elements based on int type, will be the same. But according to the first part we will have 8,039,598 excessive objects in case of the first array, consequently it will take considerable larger memory.

By the way, I cannot see if this number is real with profiler, do you have any idea how to check this?