[J3] Can multiple specific binding of a generic type-bound procedure points to one specific type-bound procedure?

[Daniel Chen]

Hi Kurt,
Yeah, it makes sense to me.
I missed the overriding part of the story. It would be ambiguous.

Thanks,
Daniel

From: J3 <j3-bounces at mailman.j3-fortran.org> on behalf of Kurt W Hirchert via J3 <j3 at mailman.j3-fortran.org>
Date: Tuesday, July 15, 2025 at 11:48 AM..
To: Daniel Chen via J3 <j3 at mailman.j3-fortran.org>
Cc: Kurt W Hirchert <kurthirchert at gmail.com>
Subject: [EXTERNAL] Re: [J3] Can multiple specific binding of a generic type-bound procedure points to one specific type-bound procedure?
It appears nonconforming to me, not specifically because assign and otherassign are the same procedure, but because they have the same interface and thus violate the rules for creating unambiguous generics. While it could be argued that this

It appears nonconforming to me, not specifically because assign and otherassign are the same procedure, but because they have the same interface and thus violate the rules for creating unambiguous generics.  While it could be argued that this ambiguity is benign for type(dt), since either resolution selects the same actual procedure (myassign), this would not be true for class(dt), because assign and otherassign can be separately overridden in extensions of dt.

Does my reasoning sound right yo you?

-Kurt

On 7/15/2025 8:32 AM, Daniel Chen via J3 wrote:
Hello all,

Is the following program legal?

```
module m
  type dt
    integer i
  contains
    generic :: ASSIGNMENT(=) => assign
    procedure, pass :: assign => myassign
    generic :: ASSIGNMENT(=) => otherassign
    procedure, pass :: otherassign => myassign
  end type
contains
  subroutine myassign(x,y)
    class(dt), intent(out) :: x
    integer, intent(in) :: y
    x%i = y + 1
  end subroutine
```

Generic defined ASSIGNMENT(=) has 2 specific binding names (“assign” and “otherassign”), but they all point to the same specific module procedure “myassign”.
It seems OK to me as I can’t find any wording in the standard to disallow it.
Any comments are very welcome!

Thanks,
Daniel


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