Add a FortranPattern: CoR(Chain of Responsibility)

README.md

@@ -25,7 +25,7 @@ Tested on: GNU Fortran (GCC) 4.8.
 - [ ] Proxy
 
 #### Behavioral Patterns
-- [ ] Chain of Responsibility
+- [x] Chain of Responsibility
 - [ ] Command
 - [ ] Interpreter
 - [ ] Iterator

behavioral/chain_of_responsibility/CoR_main.f90

@@ -0,0 +1,33 @@
+!> CoR: Patient visiting hospital
+program test_CoR
+
+    use hospital_CoR
+
+    type(cashier) :: c
+    type(medical) :: m
+    type(doctor) :: d
+    type(reception) :: r
+
+    type(patient) :: p1, p2
+
+    !> Set next for departments
+    call m%set_next(c)
+    call d%set_next(m)
+    call r%set_next(d)
+
+    p1 = patient("abc",.true.,.true.,.true.,.true.)
+    !> Patient visiting
+    print *, "> Patient `"//p1%name//"` : "
+    call r%execute(p1)
+
+    p2 = patient("def",.true.,.false.,.false.,.false.)
+    !> Patient visiting
+    print *, "> Patient `"//p2%name//"` : "
+    call r%execute(p2)
+
+    !> Optional statements
+    deallocate(m%next)
+    deallocate(d%next)
+    deallocate(r%next)
+
+end program test_CoR

behavioral/chain_of_responsibility/CoR_module.f90

@@ -0,0 +1,160 @@
+!> CoR: Hospital departments
+module hospital_CoR
+
+    implicit none
+    private
+
+    public :: patient, department, reception, doctor, medical, cashier
+
+    type patient
+        character(:), allocatable :: name
+        logical :: registration_done
+        logical :: doctor_check_up_done
+        logical :: medicine_done
+        logical :: payment_done
+    end type patient
+
+    type, abstract :: department
+    contains
+        procedure(execute_procedure), deferred :: execute
+        procedure(set_next_procedure), deferred :: set_next
+    end type department
+
+    abstract interface
+        subroutine execute_procedure(self, p)
+            import department, patient
+            class(department), intent(inout) :: self
+            type(patient), intent(inout) :: p
+        end subroutine execute_procedure
+        subroutine set_next_procedure(self, next)
+            import department
+            class(department), intent(inout) :: self
+            class(department), intent(inout) :: next
+        end subroutine set_next_procedure
+    end interface
+
+    type, extends(department) :: reception
+        class(department), pointer :: next
+    contains
+        procedure :: execute => reception_execute
+        procedure :: set_next => reception_set_next
+    end type reception
+
+    type, extends(department) :: doctor
+        class(department), pointer :: next
+    contains
+        procedure :: execute => doctor_execute
+        procedure :: set_next => doctor_set_next
+    end type doctor
+
+    type, extends(department) :: medical
+        class(department), pointer :: next
+    contains
+        procedure :: execute => medicine_execute
+        procedure :: set_next => medicine_set_next
+    end type medical
+
+    type, extends(department) :: cashier
+        class(department), pointer :: next
+    contains
+        procedure :: execute => cashier_execute
+        procedure :: set_next => cashier_set_next
+    end type cashier
+
+contains
+
+    subroutine reception_execute(self, p)
+        class(reception), intent(inout) :: self
+        type(patient), intent(inout) :: p
+
+        if (p%registration_done) then
+            print *, "Patient registration already done.✔️"
+            call self%next%execute(p)
+            return
+        end if
+
+        print *, "Reception registering patient."
+        p%registration_done = .true.
+        call self%next%execute(p)
+
+    end subroutine reception_execute
+
+    subroutine reception_set_next(self, next)
+        class(reception), intent(inout) :: self
+        class(department), intent(inout) :: next
+
+        allocate(self%next, source=next)
+
+    end subroutine reception_set_next   
+
+    subroutine doctor_execute(self, p)
+        class(doctor), intent(inout) :: self
+        type(patient), intent(inout) :: p
+
+        if (p%doctor_check_up_done) then
+            print *, "Doctor checkup already done.✔️"
+            call self%next%execute(p)
+            return
+        end if
+
+        print *, "Doctor checking patient."
+        p%doctor_check_up_done = .true.
+        call self%next%execute(p)
+
+    end subroutine doctor_execute
+
+    subroutine doctor_set_next(self, next)
+        class(doctor), intent(inout) :: self
+        class(department), intent(inout) :: next
+
+        allocate(self%next, source=next)
+
+    end subroutine doctor_set_next   
+
+    subroutine medicine_execute(self, p)
+        class(medical), intent(inout) :: self
+        type(patient), intent(inout) :: p
+
+        if (p%medicine_done) then
+            print *, "Medicine already given to patient.✔️"
+            call self%next%execute(p)
+            return
+        end if
+
+        print *, "Medical giving medicine to patient."
+        p%medicine_done = .true.
+        call self%next%execute(p)
+
+    end subroutine medicine_execute
+
+    subroutine medicine_set_next(self, next)
+        class(medical), intent(inout) :: self
+        class(department), intent(inout) :: next
+
+        allocate(self%next, source=next)
+
+    end subroutine medicine_set_next   
+
+    subroutine cashier_execute(self, p)
+        class(cashier), intent(inout) :: self
+        type(patient), intent(inout) :: p
+
+        if (p%payment_done) then
+            print *, "Payment Done.✔️"
+            return
+        end if
+
+        print *, "Cashier getting money from patient."
+        p%payment_done = .true.
+
+    end subroutine cashier_execute
+
+    subroutine cashier_set_next(self, next)
+        class(cashier), intent(inout) :: self
+        class(department), intent(inout) :: next
+
+        allocate(self%next, source=next)
+
+    end subroutine cashier_set_next   
+
+end module hospital_CoR