1. Support for OOP in Fortran (90 and some 95)
By Samuel Robinson

2. Support for OOP in Fortran(90)
~General Characteristics
-Backwards compatible with Fortran 77
-Classes are supported (keyword: module)
-Supports static and dynamic binding
(bdstatic, bdynamic) and heap dynamic
variables
-Supports polymorphism /dynamic binding (Fortran 95)
Support for OOP in Fortran(90)

3. Support for OOP in Fortran (90)
Inheritance
-Single – only one member inherits
-Selective Single – specifies what to inherit
-Single with Local Renaming
-Multiple Selective

4. Single Inheritance Module new_class_name Use base_class_name
!make new attribute declarations
Contains
!declare new member definitions
End module new_class_name

5. Selective Single Inheritance
Module new_class_name
Use base_class_name; only: list_of_entities
!declare new attributes
Contains
!declare new member definitions
End module new_class_name

6. Single Inheritance with Local Renaming
Module new_class_name
Use base_class name; local_name=> base_entity_name
!new attribute declarations
Contains
!new member declarations
End module new_class_name

7. Multiple Selective Inheritance with Renaming
Module new_class_name
Use base1_class_name
Use base2_class_name
Use base3_class_name; list of entities
Use base4_class_name, local_name => base entity name
!new member definitions
Contains
End module new_class_name

8. Examples module student !declares student class INTEGER idnumber
end module student
module class !declares student class
INTEGER classnumber
CHARACTER description
end module class
module student_information !new class
use student
use class, only: classnumber
end module student_information

9. Examples module student INTEGER idnumber contains subroutine grade
grade = average*4
end subroutine grade
end module student
module class
use student, classnumber =>idnumber
end module class
Examples

10. Public and Private Source: IncyWincy.com module Room_class
implicit none
public
type Room
private
integer :: roomNumber
logical, dimension(4) :: walls
end type Room
integer, parameter :: NORTH =1, SOUTH = 2..
contains

11. This Source: IncyWincy.com
To make sure that a type is given the correct procedure, an object of that type needs to be passed. To do this, give the object the name “this” and make it first argument
Ex:
Subroutine new_Room (this, roomNumber,
N,S, E, W)
type(Room) :: this
...

12. Support for OOP in Fortran(95)
Dynamic Binding – lets a single object refer to any member of an inheritance hierarchy and allows a procedure to resolve at run time whch object is being referred to
Necessary : id mechanism to keep track of the class of the object and method lookup to select the right procedure to execute

13. Polymorphic Type Source: rsimplifiedRT.cwk type poly_stopwatch private
type(stopwatch), pointer :: s
Type (parallel_stopwatch), pointer :: p
end type poly_stopwatch

14. Use poly_stopwatch_class
type(stopwatch) s
type(parallel_stopwatch) p
type(poly_stopwatch) sw
call new_stopwatch(s)
call new_parallel_stopwatch(p)
sw = poly(s)
call split(sw, 'bar')
call bar()
call report(sw, 6)
sw = poly(p)
call split(sw, 'foo')
call foo()

15. Evaluation ~Fortran is object based, but not object oriented.
-Inheritance and run time polymorphism are not directly supported, rather they are emulated.
-Different, yet the similar.