Re: Wide_[Wide_]Character

["Peter C. Chapin" <pchapin@sover.net>]

Dale Stanbrough wrote:

> I can't see any implication that would cause me to think 
> Wide_Wide_Character is definitely UCS-4 (and not UTF-16).


Well, section 3.5.2 (Character Types) in the Ada 2005 reference manual says:

   "The predefined type Wide_Wide_Character is a character type whose 
values correspond to the 2147483648 code positions of the ISO/IEC 
10646:2003 character set. Each of the graphic_characters has a 
corresponding character_literal in Wide_Wide_Character. The first 65536 
values of Wide_Wide_Character have the same character_literal or 
language-defined name as defined for Wide_Character."

I understand that this doesn't speak to the issue of encoding, but 
perhaps that is intended to be left unspecified. In any event it seems 
fairly clear that you should be able to store any of 2147483648 values 
in a single Wide_Wide_Character variable. Doesn't that mean 
Wide_Wide_Character needs to be (at least) 32 bits?

Peter