Re: Char type verification

[Georg Bauhaus <bauhaus@futureapps.de>]

On Wed, 2006-11-15 at 14:00 -0800, KE wrote:
> Hi
> 
> Assume that I have the following C code:
> 
> #include <stdio.h>
> 
> #define uchar   unsigned char
> 
> 
> static uchar UCASE[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";

This is the character range 'A' .. 'Z'.
You can simply write
  c in 'A' .. 'Z'
in any Boolean context where c is of type Character.

Or use Ada.Characters.Handling.Is_Upper(c), if you want
to include characters outside 7bit ASCII.

The C type char, which IIRC might start at -127 or
at 0, has an implementation defined representation,
and is a bit vague. The Ada standard frowns upon vague
things, hence Ada's character type does not have
theses issues. OTOH, for interfacing with C,
look at the standard package Interfaces.C.

For more general uses, there are standard packages
Ada.Strings.Maps, Ada.Strings.Maps.Constants,
Ada.Characters.Handling, and Ada.Characters.Latin_1.
There are all kinds of character predicates and
translation subprograms.

There are variants for Wide_Character, covering
the BMP of ISO 10646.

Ada 2005, in addition supports Unicode and related
subprograms.