Ada 95 Modular Types Question 4.5.1(2)

Ada 95 Modular Types Question 4.5.1(2)

[Thomas A Peterson]

If I define a modular type in a package and use the type in another
compilation unit are the logical operators visible by default?

The GNAT compiler and Rational Apex compiler differ with respect to the
visibility of the logical operators and I would like to send someone a bug
report.

Here is an example...

package Example is 

  type Unsigned_Byte is mod 256;

end Example;


with Example;
procedure Test_Example is
  A : Example.Unsigned_Byte := 11;
  B : Example.Unsigned_Byte := 37;
  C : Example.Unsigned_Byte;
begin
  C := A or B;
--C := Example."or"(A, B);
end Test_Example;

Thanks, Tom

Re: Ada 95 Modular Types Question 4.5.1(2)

[Tucker Taft]

Thomas A Peterson (tap@htc.honeywell.com) wrote:

: If I define a modular type in a package and use the type in another
: compilation unit are the logical operators visible by default?

There is nothing special about the logical operators of modular types.
To get direct visibility on the primitive operators of any type,
you need to "use" the package where the type is declared,
or "use type" a subtype of the type, or do local renames of the operators.

: The GNAT compiler and Rational Apex compiler differ with respect to the
: visibility of the logical operators and I would like to send someone a bug
: report.

: Here is an example...

: package Example is 

:   type Unsigned_Byte is mod 256;

: end Example;


: with Example;
: procedure Test_Example is
:   A : Example.Unsigned_Byte := 11;
:   B : Example.Unsigned_Byte := 37;
:   C : Example.Unsigned_Byte;
: begin
:   C := A or B;
           ^^
If the compiler accepts this it has a bug (albeit a "friendly" one ;-).

: --C := Example."or"(A, B);
: end Test_Example;

: Thanks, Tom

--
-Tucker Taft   stt@inmet.com   http://www.inmet.com/~stt/
Intermetrics, Inc.  Burlington, MA  USA

Re: Ada 95 Modular Types Question 4.5.1(2)

[Robert Dewar]

Gordon's example is clearly illegal, and GNAT correctly diagnoses it:

test_example.adb:7:10: operator for type "Unsigned_Byte" defined at example.ads:
3 is not directly visible
test_example.adb:7:10: use clause would make operation legal