Re: Large arrays (again), problem case for GNAT

["Dr. Adrian Wrigley" <amtw@linuxchip.demon.co.uk.uk.uk>]

On Fri, 15 Apr 2005 15:21:32 +0200, Dmitry A. Kazakov wrote:

> On Fri, 15 Apr 2005 11:49:23 GMT, Dr. Adrian Wrigley wrote:
> 
...
>> I couldn't understand why there was no decent mechanism for changing
>> the size of an array.  The resulting code was much cleaner, faster
>> and more memory efficient than using fancy data structures/container
>> libraries.
>> 
>> Why did the language not provide an equivalent of 'realloc' for
>> arrays?
> 
> I would propose:
> 
> generic
>    type Element_Type is limited private;
>    type Index_Type is (<>);
>    type Array_Type is array (Index_Type) of Element_Type;
>    type Access_Type is access Array_Type;
> procedure Ada.Array_Resize (X : in out Access_Type; Elements : Integer);
> 
> and 
> 
> generic
>    type Element_Type is private;
>    type Index_Type is (<>);
>    type Array_Type is array (Index_Type) of Element_Type;
>    type Access_Type is access Array_Type;
> procedure Ada.Array_Expand
>    (  X : in out Access_Type;
>       Elements : Natural;
>       Initial : Element_Type
>    );

This looks plausible.  Could we specify the new 'Last index instead of
the Elements parameter? (what about a new 'First index?) Maybe you'd
have difficulty creating a zero element array though.

It'd be nice if it was less verbose too. 'new' seems so simple
to use - something equally simple would be nice for resizing.
Maybe an extra parameter for new or something(?)
-- 
Adrian