Re: Ada and Unicode

[Thomas <fantome.forums.tDeContes@free.fr.invalid>]

In article <f9d91cb0-c9bb-4d42-a1a9-0cd546da436cn@googlegroups.com>,
 Vadim Godunko <vgodunko@gmail.com> wrote:

> On Sunday, April 18, 2021 at 1:03:14 AM UTC+3, DrPi wrote:

> > What's the way to manage Unicode correctly ? 
> > 
> 
> Ada doesn't have good Unicode support. :( So, you need to find suitable set 
> of "workarounds".
> 
> There are few different aspects of Unicode support need to be considered:
> 
> 1. Representation of string literals. If you want to use non-ASCII characters 
> in source code, you need to use -gnatW8 switch and it will require use of 
> Wide_Wide_String everywhere.
> 2. Internal representation during application execution. You are forced to 
> use Wide_Wide_String at previous step, so it will be UCS4/UTF32.

> It is hard to say that it is reasonable set of features for modern world.

I don't think Ada would be lacking that much, for having good UTF-8 
support.

the cardinal point is to be able to fill a 
Ada.Strings.UTF_Encoding.UTF_8_String with a litteral.
(once you got it, when you'll try to fill a Standard.String with a 
non-Latin-1 character, it'll make an error, i think it's fine :-) )

does Ada 202x allow it ?

if not, it would probably be easier if it was
    type UTF_8_String is new String;
instead of
    subtype UTF_8_String is String;


for all subprograms it's quite easy:
we just have to duplicate them with the new type, and to mark the old 
one as Obsolescent.

but, now that "subtype UTF_8_String" exists, i don't know what we can do 
for types.
(is the only way to choose a new name?)


> To 
> fix some of drawbacks of current situation we are developing new text 
> processing library, know as VSS. 
> 
> https://github.com/AdaCore/VSS

(are you working at AdaCore ?)

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