(j3.2006) Interp request for GENERIC

[Tom Clune]

In the sample code below there are two derived types defined - Base  
and Child, which EXTEND's Base.   Base defines a GENERIC with two type- 
bound procedures, and Child overrides those type bound procedures.  On  
two compilers, when the generic is invoked on an object of type child,  
the Child's type-bound procedures are invoked, while one other the  
parent's are invoked.   The former makes more intuitive sense.   The  
statements on the subject in the extant F2003 books left me more  
confused on this issue.

module ClassMod
    implicit none

    type Base
    contains
       procedure :: base_i
       procedure :: base_r8
       generic :: proc => base_i, base_r
    end type Base

    type, extends(Base) :: Child
       integer :: i
       real :: x
    contains
       procedure :: base_i  => child_i
       procedure :: base_r => child_r
    end type Child

contains

    subroutine base_i(this,i)
       class(Base) :: this
       integer :: i
       write(6,*) 'executed base_i'
    end subroutine base_i

    subroutine base_r(this,x)
       class(Base) :: this
       real :: x
       write(6,*) 'executed base_r'
    end subroutine base_r

    subroutine child_i(this,i)
       class(Child) :: this
       integer :: i
       this%i = i
       write(6,*) 'executed child_i'
    end subroutine child_i

    subroutine child_r(this,x)
       class(Child) :: this
       real :: x
       this%x = x
       write(6,*) 'executed child_r'
    end subroutine child_r

end module ClassMod

program tryit
    use ClassMod
    implicit none
    integer :: i
    real :: x
    type(Base) :: foo
    type(Child) :: bar
    i = 5
    x = 20e0
    write(6,*) 'calling Base:'
    call foo%proc(i)
    call foo%proc(x)
    write(6,*) 'calling actual procedures:'
    call bar%proc(i)
    call bar%proc(x)
end program tryit



Thanks in advance,

- Tom

Thomas Clune					
Software Integration and Visualization Office
NASA GSFC (610.3)
301-286-4635 (W)	301-286-1775 (F)
<Thomas.L.Clune at nasa.gov>