Start with a few questions
How often…
- do you need to write an application that deals with something else than ascii?
- do you need to write a multi-language application?
- do you write an application that has to be multi-language from its first version?
- have you heard that Unicode is used to represent non-ascii characters?
- have you read that Unicode is a charset? That Unicode is an encoding?
- do you see people confusing UTF-8 encoded bytestrings and Unicode data?
Do you know the difference between a collation and an encoding?
Where did you first heard of Unicode?
- At school? (really?)
- at work?
- on a trendy blog?
Have you ever, in your young days, experienced moving source files from a system in locale A to a system in locale B, edited a typo on system B, saved the files, b0rking all the non-ascii comments and… ending up wasting a lot of time trying to understand what happened? (did your editor mix things up? the compiler? the system? the… ?)
Did you end up deciding that never again you will comment your code using non-ascii characters?
Have a look at what’s being done elsewhere
Python
Did I mention on SO that I love Python? No? Well I love Python.
But until Python3.0, its Unicode support sucked. And there were all those rookie programmers, who at that time knew barely how to write a loop, getting UnicodeDecodeError and UnicodeEncodeError from nowhere when trying to deal with non-ascii characters. Well they basically got life-traumatized by the Unicode monster, and I know a lot of very efficient/experienced Python coders that are still frightened today about the idea of having to deal with Unicode data.
And with Python3, there is a clear separation between Unicode & bytestrings, but… look at how much trouble it is to port an application from Python 2.x to Python 3.x if you previously did not care much about the separation/if you don’t really understand what Unicode is.
Databases, PHP
Do you know a popular commercial website that stores its international text as Unicode?
You will (perhaps) be surprised to learn that Wikipedia backend does not store its data using Unicode. All text is encoded in UTF-8 and is stored as binary data in the Database.
One key issue here is how to sort text data if you store it as Unicode codepoints. Here comes the Unicode collations, which define a sorting order on Unicode codepoints. But proper support for collations in Databases is missing/is in active development. (There are probably a lot of performance issues, too. — IANADBA) Also, there is no widely-accepted standard for collations yet: for some languages, people don’t agree on how words/letters/wordgroups should be sorted.
Have you heard of Unicode normalization? (Basically, you should convert your Unicode data to a canonical representation before storing it) Of course it’s critical for Database storage, or local comparisons. But PHP for example only provides support for normalization since 5.2.4 which came out in August 2007.
And in fact, PHP does not completely supports Unicode yet. We’ll have to wait PHP6 to get Unicode-compatible functions everywhere.
So, why isn’t everything we do in Unicode?
- Some people don’t need Unicode.
- Some people don’t care.
- Some people don’t understand that they will need Unicode support later.
- Some people don’t understand Unicode.
- For some others, Unicode is a bit like accessibility for webapps: you start without, and will add support for it later
- A lot of popular libraries/languages/applications lack proper, complete Unicode support, not to mention collation & normalization issues. And until all items in your development stack completely support Unicode, you can’t write a clean Unicode application.
The Internet clearly helps spreading the Unicode trend. And it’s a good thing. Initiatives like Python3 breaking changes help educating people about the issue. But we will have to wait patiently a bit more to see Unicode everywhere and new programmers instinctively using Unicode instead of Strings where it matters.
For the anecdote, because FedEx does not apparently support international addresses, the Google Summer of Code ’09 students all got asked by Google to provide an ascii-only name and address for shipping. If you think that most business actors understand stakes behind Unicode support, you are just wrong. FedEx does not understand, and their clients do not really care. Yet.