F2003: pass disallowed for procedure pointer components?

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Hello,


In a discussion with Andy Vaught concerning procedure pointer components the issues
described in the following came up:

Is the following module

module foo
implicit none
private
type, public :: tt
double precision :: a, b
procedure(fun), pointer, pass :: f
end type
abstract interface
subroutine fun(this, x)
import :: tt
type (tt), intent(inout) :: this
double precision, intent(in) :: x
end subroutine
end interface
end module

standard conforming? Consulting the standard appears to indicate that this is
not the case, since in 12.3.2.3 we have:

24 C1212 (R1215) The name shall be the name of an abstract interface or of a procedure that has an
25 explicit interface. If name is declared by a procedure-declaration-stmt it shall be previously
26 declared. If name denotes an intrinsic procedure it shall be one that is listed in 13.6 and not
27 marked with a bullet (�).

provided the second sentence of C1212 can be interpreted as having the same meaning as
"A /name/ referenced by a /procedure-declaration-stmt/ shall be previously declared."


Going further, it is also not possible to have

module foo
implicit none
private
abstract interface
subroutine fun(this, x)
import :: tt
type (tt), intent(inout) :: this
double precision, intent(in) :: x
end subroutine
end interface
type, public :: tt
double precision :: a, b
procedure(fun), pointer, pass :: f
end type
end module

since in 12.3.2.1 we have (p260:3-7):

9 The IMPORT statement specifies that the named entities from the host scoping unit are accessible in
10 the interface body by host association. An entity that is imported in this manner and is defined in the
11 host scoping unit shall be explicitly declared prior to the interface body. The name of an entity made
12 accessible by an IMPORT statement shall not appear in any of the contexts described in 16.4.1.3 that
13 cause the host entity of that name to be inaccessible.


All this seems to indicate that it is not possible to have a passed object dummy argument for a procedure
pointer component notwithstanding the fact that

(i) 4.5.3.3 explicitly mentions the passed object dummy argument as being applicable also for procedure
pointer components
(ii) 12.4.1.1 (with the correction F03/0043 from 05-016) confirms this.

Finally, if the second sentence of C1212 simply was misunderstood by me, the example is probably still
non-conforming due to C453 in 4.5.3.3, according to which the passed object dummy must be polymorphic, i. e.

class(tt), intent(in) :: this

Why was this deemed necessary also for procedure pointer components?


References used:

http://j3-fortran.org/doc/2003_Committee_Draft/04-007.pdf
http://j3-fortran.org/doc/standing/016%20Completed%20Fortran%202003%20Interpretations/05-016.txt

Regards

Reinhold Bader
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