Re: Ada and Unicode

[Maxim Reznik <reznikmm@gmail.com>]

воскресенье, 18 апреля 2021 г. в 01:03:14 UTC+3, DrPi:
> 
> Any way to use source code encoded in UTF-8 ? 

Yes, with GNAT just use "-gnatW8" for compiler flag (in command line or your project file):

--  main.adb:
with Ada.Wide_Wide_Text_IO;

procedure Main is
   Привет : constant Wide_Wide_String := "Привет";
begin
   Ada.Wide_Wide_Text_IO.Put_Line (Привет);
end Main;

$ gprbuild -gnatW8 main.adb
$ ./main 
Привет


> In some languages, it is possible to set a tag at the beginning of the 
> source file to direct the compiler which encoding to use. 

You can do this with putting the Wide_Character_Encoding pragma (This is a GNAT specific pragma) at the top of the file. Take a look:

--  main.adb:
pragma Wide_Character_Encoding (UTF8);

with Ada.Wide_Wide_Text_IO;

procedure Main is
   Привет : constant Wide_Wide_String := "Привет";
begin
   Ada.Wide_Wide_Text_IO.Put_Line (Привет);
end Main;

$ gprbuild main.adb
$ ./main 
Привет



> What's the way to manage Unicode correctly ? 
> 

You can use Wide_Wide_String and Unbounded_Wide_Wide_String type to process Unicode strings. But this is not very handy. I use the Matreshka library for Unicode strings. It has a lot of features (regexp, string vectors, XML, JSON, databases, Web Servlets, template engine, etc.). URL: https://forge.ada-ru.org/matreshka

> Regards, 
> Nicolas