Re: some simple questions

[Jeffrey Carter <jrcarter@acm.org>]

Steve wrote:
> 
> If you add:
>     procedure free is new ada.unchecked_deallocation( integer, pint );
> Then free(pi) works.

It seems more important to ask why the OP is using an access type. 
Pointers are needed far less often in Ada than in other languages; since 
the OP indicates that he knows [at least] one of these other languages, 
it is likely that this is a mind-set problem rather than a syntax question.

>>and last one
>>what's "std::system("clear");" translated to Ada
>>(OS Linux)
> 
> I can only guess on this one (you'll probably get an answer from someone
> else).
> Here's my guess:
>   If the profile for system looks something like:
>   int system( char *str );
> 
> Then in Ada you can use that function by declaring:
> 
>   function System( str : Interfaces.C.Strings.Char_Array_Access ) return
> integer;
>   pragma Import( C, System, "system" );

There's no need to use Char_Array_Access here; you can simply use 
Char_Array and the compiler will pass it correctly. You might want to 
avoid the name System, since it's the name of a standard package.

I have seen "system" imported and used successfully on Linux and 
Windows. You might also want to look for a compiler dependent package 
for access to the OS to do this. For example, GNAT provides the package 
GNAT.OS_Lib.

-- 
Jeff Carter
"Sons of a silly person."
Monty Python & the Holy Grail