json_value_reverse Subroutine

private subroutine json_value_reverse(json, p)

Reverse the order of the children of an array or object.


Type IntentOptional AttributesName
class(json_core), intent(inout) :: json
type(json_value), pointer:: p


Source Code

Source Code

    subroutine json_value_reverse(json,p)

    implicit none

    class(json_core),intent(inout) :: json
    type(json_value),pointer       :: p

    type(json_value),pointer :: tmp       !! temp variable for traversing the list
    type(json_value),pointer :: current   !! temp variable for traversing the list
    integer(IK)              :: var_type  !! for getting the variable type

    if (associated(p)) then

        call json%info(p,var_type=var_type)

        ! can only reverse objects or arrays
        if (var_type==json_object .or. var_type==json_array) then

            current => p%children
            p%tail => current

            ! Swap next and previous for all nodes:
                if (.not. associated(current)) exit
                tmp              => current%previous
                current%previous => current%next
                current%next     => tmp
                current          => current%previous
            end do

            if (associated(tmp)) then
                p%children => tmp%previous
            end if

        end if

    end if

    end subroutine json_value_reverse