Re: [boost] Work that has been done on Unicode

From: loufoque (mathias.gaunard_at_[hidden])
Date: 2006-09-15 20:22:20

Since no one has old code for reuse, I will start to write a few usable 
tools from scratch.
Note that I am not an Unicode expert nor a C++ guru.
I am just willing to work in that area and hope my code could be useful 
to some.

Feel free to comment and give ideas, since I think the design is the 
most important thing first, especially for usage with boost, even though 
this topic has already been discussed a few times.

string/wstring is not really suited to contain unicode data, since of 
limitations of char_traits, the basic_string interface, and the 
dependance on locales of the string and wstring types.
I think it is better to consider the string, char[], wstring and 
wchar_t[] types to be in the system locales and to use a separate type 
for unicode strings.

The aim would then be to provide an abstract unicode string type 
independent from C++ locales on the grapheme clusters level, while also 
giving access to lower levels.
It would only handle unicode in a generic way at the beginning (no 
locales or tailored things).
This string could maintain the characters in a normalized form (which 
means potential loss of information about singleton characters) in order 
to allow more efficient comparison and searching.

It would use a policy-based design in order to be as generic as possible 
and therefore customizable on many levels, allowing to use the data 
structure and encoding you need for interfacing with other libraries.

The policy-based design would also provide functionality similar to 
flex_string, to explicitly choose whether to use COW or other 
optimizations depending on the situation.

There would also be a const versions, following the const_string design.

Just like super_string, the class would bundle algorithms from 
string_algo, since it can probably implement them in a more efficient 
way than iterating over the grapheme clusters.