Re: ada language

[Lutz Donnerhacke <lutz@iks-jena.de>]

* satish umakar wrote:
> how to convert a array of characters(characters stored in a array read
> from a file) to a string type.

The language defines:
  type String is array (Positive range <>) of Characters;
So there is no difference between an array of Characters and a String,
besides the String is a new type and the array is a different type.
Therefore simply assign it, as long as the offsets does not cause a
constraint problem:

procedure t is
   type Array_of_Character is array (Integer range <>) of Character;
   a : Array_of_Character := (-3 => 'H', -2 => 'e', -1|0 => 'l', 1 => 'o');
   b : constant Array_of_Character (1 .. a'Length) := a;
   s : String := String (b);
begin
   null;
end t;

If the domains of the offset types do not overlap, you have a problem. You
will even have a problem when copying takes to much time or ressources:

procedure t is
   type Negative is new Integer range Integer'First .. -1;
   type Array_of_Character is array (Negative range <>) of Character;
   a : Array_of_Character := (-5 => 'H', -4 => 'e', -3|-2 => 'l', -1 => 'o');
   s : String (1 .. a'Length);
   pragma Import (Ada, s);       -- Suppress initialising.
   for s'Address use a'Address;  -- Map array content.
begin
   null;
end t;