io - 写语句不能在派生类型的用户定义格式化 I/O 过程中生成新行

Question

我想在我的 Fortran 代码中为派生类型实现用户定义的 I/O 过程。但是，write这些过程中的语句不能在两个连续的 write 之间产生新行陈述。派生类型和过程定义如下。

模块:

module station_module
    implicit none

    character(8), parameter :: FmtFloat = '(5E15.7)'

    type :: station
        integer, private :: ns = 0
        real, public, allocatable :: xloc(:), yloc(:), zloc(:)
    contains
        procedure, public :: import_station
        procedure, public :: export_station
        procedure, private :: read_station
        generic, public :: read (formatted) => read_station
        procedure, private :: write_station
        generic, public :: write (formatted) => write_station
        final :: destruct_station
    end type station

    interface station
        module procedure new_station
    end interface station

contains

    function new_station(n) result(t)
        implicit none
        integer, intent(in) :: n
        type(station) :: t

        if (n > 0) then
            allocate (t%zloc(n))
            allocate (t%yloc(n))
            allocate (t%xloc(n))
            t%ns = n
        end if
    end function new_station

    subroutine read_station(dtv, unit, iotype, vlist, iostat, iomsg)
        implicit none
        class(station), intent(inout) :: dtv
        integer, intent(in) :: unit
        character(*), intent(in) :: iotype
        integer, intent(in) :: vlist(:)
        integer, intent(out) :: iostat
        character(*), intent(inout) :: iomsg

        call dtv%import_station(unit)

        iostat = 0
    end subroutine read_station

    subroutine import_station(this, unit)
        implicit none
        class(station), intent(inout) :: this
        integer, intent(in) :: unit
        character(256) :: header, footer
        integer ns

        read (unit, '(A)') header !> Header
        read (unit, *) ns
        if (ns > 0) then
            if (allocated(this%zloc)) then
                deallocate (this%zloc)
            end if
            allocate (this%zloc(ns))
            read (unit, *) this%zloc

            if (allocated(this%yloc)) then
                deallocate (this%yloc)
            end if
            allocate (this%yloc(ns))
            read (unit, *) this%yloc

            if (allocated(this%xloc)) then
                deallocate (this%xloc)
            end if
            allocate (this%xloc(ns))
            read (unit, *) this%xloc

            this%ns = ns
        end if
        read (unit, '(A)') footer !> Footer
    end subroutine import_station

    subroutine export_station(this, unit)
        implicit none
        class(station), intent(in) :: this
        integer, intent(in) :: unit

        write (unit, '(A)') ">STATION INFO"
        write (unit, '(I6)') this%ns
        write (unit, *) "Z:"
        write (unit, FmtFloat) this%zloc
        write (unit, *) "Y:"
        write (unit, FmtFloat) this%yloc
        write (unit, *) "X:"
        write (unit, FmtFloat) this%xloc
        write (unit, '(A)') ">END STATION"
    end subroutine export_station

    subroutine write_station(dtv, unit, iotype, vlist, iostat, iomsg)
        implicit none
        class(station), intent(in) :: dtv
        integer, intent(in) :: unit
        character(*), intent(in) :: iotype
        integer, intent(in) :: vlist(:)
        integer, intent(out) :: iostat
        character(*), intent(inout) :: iomsg

        call dtv%export_station(unit)

        iostat = 0
    end subroutine write_station

    subroutine destruct_station(this)
        implicit none
        type(station), intent(inout) :: this

        if (allocated(this%xloc)) then
            deallocate (this%xloc)
        end if
        if (allocated(this%yloc)) then
            deallocate (this%yloc)
        end if
        if (allocated(this%zloc)) then
            deallocate (this%zloc)
        end if
        this%ns = 0
    end subroutine destruct_station

end module station_module

我们可以看到用户自定义的 格式化写入 语句只调用一个名为 export_station 的常规子程序，我希望这两种方式都得到相同的结果。

这是我的 测试程序:

program Test
    use station_module
    implicit none
    type(station) :: pt, pt1, pt2

    pt = station(4)

    write(*, *) pt

    call pt%export_station(6)

end program Test

输出:

 >STATION INFO     4Z:  0.0000000E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00
 Y:  0.0000000E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00X:  0.0000000E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00>END STATION
>STATION INFO
     4
 Z:
  0.0000000E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00
 Y:
  0.0000000E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00
 X:
  0.0000000E+00  0.0000000E+00  0.0000000E+00  0.0000000E+00
>END STATION

常规子程序 export_station产生我所期望的。在两个 write 之间产生新的生产线语句，而 write派生类型的声明没有。

Answer 1

英特尔论坛上也有人问过这个问题。我在那里回答。“用户定义的派生类型 I/O 都是非高级的(你不能改变它)。如果你想要换行，你必须明确地写出来(例如使用/格式。)”