Re: When/Why can a compiler reject an operator but accept a name?

[Robert A Duff <bobduff@shell01.TheWorld.com>]

Wes Groleau <wesgroleau@despammed.com> writes:

> In package G I have:
> 
>     type List_Type is array (Natural range <>) of Item;
> 
>     type Order is access function (Left, Right : in Item) return
> Boolean;
> 
>     procedure Sort (List : in out List_Type; Sequence : in Order);
>     
> 
> In procedure P I had:
> 
>     package I is new G (Item);
> 
>     function "<" (Left, Right : in Item) return Boolean is
> 
>     .....
>     
>     I.Sort (List => List, Sequence => "<"'Access);
> 
>     
> Compiler rejected it, saying:
> 
>    "<" has no definition that matches function (Left, Right : in Item)
> return Boolean [RM_95 3.10.2(32)]
>    
> I replaced "<" with Ord_Check (no other changes), and
> the compiler accepted it.

Sounds like a compiler bug, although I can't be sure without seeing all
the code (e.g., you didn't show the code for Ord_Check).

> Does using an operator instead of a name make the
> function Intrinsic?

No.

> If not, there is no support for rejection in 3.10.2(32)
> Is there any reason elsewhere in the RM to justify this
> odd behavior?
> 
> (Certainly either way, the message could be improved!)

True.  Show us a complete example.

- Bob