Ada.Containers.Vectors

Ada.Containers.Vectors

[hnptz]

Here is my code:

with Ada.Containers; use Ada.Containers;
with Ada.Containers.Vectors;
package RGF is
   package IV is new Vectors(Natural,Integer);
   use IV;
procedure GenerateRGF(m : Integer;
                        f : in out Vector);
end RGF;

package body RGF is
   use IV;
procedure GenerateRGF(m : Integer;
                      f : in out Vector) is
      done : Boolean := False;
      fmax : Vector;
      j    : Integer;
   begin
      for i in 1..m loop
         f(i):=1;
         fmax(i) := 2;
      end loop;
      while not done loop
         j := m+1;
         loop
            j := j-1;
            exit when f(j) /= fmax(j);
         end loop;
         if j > 1 then
            f(j) := f(j)+1;
            for i in j+1 .. m loop
               f(i):=1;
               if f(j) = fmax(j) then
                  fmax(i):=fmax(j)+1;
               else
                  fmax(i):=fmax(j);
               end if;
            end loop;
         else
            done := True;
         end if;
      end loop;
   end GenerateRGF;

end RGF;

As a result I get "ambiguous operands for equality" for /= and =. How to resolve these ambiguities?

Best,

Gilbert

Re: Ada.Containers.Vectors

[Per Sandberg]

Hi
A answer is that the compiler don't know if it should use the "=" for
"Constant_Reference_Type'(F (J)))" or "Integer'(F (J))".
Its a bit like:
---------------------------------------
procedure put(Item : Integer);
procedure put(Item : Long_Integer);
procedure put(Item : Long_Long_Integer);
----------------------

And then in the code:
put(2);
-- This wont compile you have to state one of the following:

put(Integer'(2));
put(Long_Integer'(2));
put(Long_Long_Integer'(2));

/Per




Den 2017-06-26 kl. 18:39, skrev hnptz@yahoo.de:
> Here is my code:
> 
> with Ada.Containers; use Ada.Containers;
> with Ada.Containers.Vectors;
> package RGF is
>     package IV is new Vectors(Natural,Integer);
>     use IV;
> procedure GenerateRGF(m : Integer;
>                          f : in out Vector);
> end RGF;
> 
> package body RGF is
>     use IV;
> procedure GenerateRGF(m : Integer;
>                        f : in out Vector) is
>        done : Boolean := False;
>        fmax : Vector;
>        j    : Integer;
>     begin
>        for i in 1..m loop
>           f(i):=1;
>           fmax(i) := 2;
>        end loop;
>        while not done loop
>           j := m+1;
>           loop
>              j := j-1;
>              exit when f(j) /= fmax(j);
>           end loop;
>           if j > 1 then
>              f(j) := f(j)+1;
>              for i in j+1 .. m loop
>                 f(i):=1;
>                 if f(j) = fmax(j) then
>                    fmax(i):=fmax(j)+1;
>                 else
>                    fmax(i):=fmax(j);
>                 end if;
>              end loop;
>           else
>              done := True;
>           end if;
>        end loop;
>     end GenerateRGF;
> 
> end RGF;
> 
> As a result I get "ambiguous operands for equality" for /= and =. How to resolve these ambiguities?
> 
> Best,
> 
> Gilbert
> 
> 
> 

Re: Ada.Containers.Vectors

[G.B.]

On 26.06.17 18:39, hnptz@yahoo.de wrote:
> As a result I get "ambiguous operands for equality" for /= and =. How to resolve these ambiguities?

A bit of a guess, it might be that the message is not
obviously about resolving equality; if I rewrite

exit when f.element(j) /= fmax(j);
...

and

if f.element(j) = fmax(j) then
...

then my compiler responds differently. If implicit_dereference of
holders is going on under the hood, this all might be an effect
of a new feature, and the message could be improved by your
compiler maker.